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Peng Z, Huang Y, Zheng K, Min Y, Zhao H, Pi M, Song F, Zheng C, Zhang Y, Chang Z, Wang Y. Slow-Light-Enhanced Polarization Division Multiplexing Infrared Absorption Spectroscopy for On-Chip Wideband Multigas Detection in a 1D Photonic Crystal Waveguide. Anal Chem 2024; 96:3445-3453. [PMID: 38364860 DOI: 10.1021/acs.analchem.3c04793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2024]
Abstract
Slow-light photonic crystal waveguide (PCW) gas sensors based on infrared absorption spectroscopy play a pivotal role in enhancing the on-chip interaction between light and gas molecules, thereby significantly boosting sensor sensitivity. However, two-dimensional (2D) PCWs are limited by their narrow mode bandwidth and susceptibility to polarization, which restricts their ability for multigas measurement. Due to quasi-TE and quasi-TM mode guiding characteristics in one-dimensional (1D) PCW, a novel slow-light-enhanced polarization division multiplexing infrared absorption spectroscopy was proposed for on-chip wideband multigas detection. The optimized 1D PCW gas sensor experimentally shows an impressive slow-light mode bandwidth exceeding 100 nm (TM, 1500-1550 nm; TE, 1610-1660 nm) with a group index ranging from 4 to 25 for the two polarizations. The achieved bandwidth in the 1D PCW is 2-3 times that of the reported quasi-TE polarized 2D PCWs. By targeting the absorption lines of different gas species, multigas detection can be realized by modulating the lasers and demodulating the absorption signals at different frequencies. As an example, we performed dual-gas measurements with the 1D PCW sensor operating in TE mode at 1.65 μm for methane (CH4) detection and in TM mode at 1.53 μm for acetylene (C2H2) detection. The 1 mm long sensor achieved a remarkable limit of detection (LoD) of 0.055% for CH4 with an averaging time of 17.6 s, while for C2H2, the LoD was 0.18%. This polarization multiplexing sensor shows great potential for on-chip gas measurement because of the slow-light enhancement in the light-gas interaction effect as well as the large slow-light bandwidth for multigas detection.
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Affiliation(s)
- Zihang Peng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Yijun Huang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Kaiyuan Zheng
- Department of Electrical Engineering and Photonics Research Institute, The Hong Kong Polytechnic University, Hong Kong 518060, China
| | - Yuting Min
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Huan Zhao
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Mingquan Pi
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Fang Song
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Chuantao Zheng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Yu Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Zhiyong Chang
- Key Laboratory of Bionic Engineering, Ministry of Education, College of Biological and Agricultural Engineering, Jilin University, Changchun 130022, China
| | - Yiding Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
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Guan G, Liu A, Wu X, Zheng C, Liu Z, Zheng K, Pi M, Yan G, Zheng J, Wang Y, Tittel FK. Near-Infrared Off-Axis Cavity-Enhanced Optical Frequency Comb Spectroscopy for CO 2/CO Dual-Gas Detection Assisted by Machine Learning. ACS Sens 2024; 9:820-829. [PMID: 38288631 DOI: 10.1021/acssensors.3c02146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Cavity-enhanced direct frequency comb spectroscopy (CE-DFCS) is widely used as a highly sensitive gas sensing technology in various gas detection fields. For the on-axis coupling incidence scheme, the detection accuracy and stability are seriously affected by the cavity-mode noise, and therefore, stable operation inevitably requires external electronic mode-locking and sweeping devices, substantially increasing system complexity. To address this issue, we propose off-axis cavity-enhanced optical frequency comb spectroscopy from both theoretical and experimental aspects, which is applied to the detection of single- and dual-gas of carbon monoxide (CO) and carbon dioxide (CO2) in the near-infrared. An erbium-doped fiber frequency comb with a repetition frequency of ∼41.709 MHz is coupled into a resonant cavity with a length of ∼360 mm in an off-axis manner, exciting numerous high-order modes to effectively suppress cavity-mode noise. The performance of multiple machine learning models is compared for the inversion of a single/dual gas concentration. A few absorbance spectra are collected to build a sample data set, which is then utilized for model training and learning. The results demonstrate that the Particle Swarm Optimization Support Vector Machine (PSO-SVM) model achieves the highest predictive accuracy for gas concentration and is ultimately applied to the detection system. Based on Allan deviation, the detection limit for CO in single-gas detection can reach 8.247 parts per million by volume (ppmv) by averaging 87 spectra. Meanwhile, for simultaneous CO2/CO measurement with highly overlapping absorbance spectra, the LoD can be reduced to 13.196 and 4.658 ppmv, respectively. The proposed optical gas sensing technique indicates the potential for the development of a field-deployable and intelligent sensor system capable of simultaneous detection of multiple gases.
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Affiliation(s)
- Gangyun Guan
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, P.R. China
| | - Anqi Liu
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, P.R. China
| | - Xuyang Wu
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, P.R. China
| | - Chuantao Zheng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, P.R. China
| | - Zhiwei Liu
- Research Center for Optical Fiber Sensing, Zhejiang Laboratory, Hangzhou 311100, P.R. China
| | - Kaiyuan Zheng
- Photonics Research Center, The Hong Kong Polytechnic University Shenzhen Research Institute, Shenzhen 518057, P.R. China
| | - Mingquan Pi
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, P.R. China
| | - Guofeng Yan
- Research Center for Optical Fiber Sensing, Zhejiang Laboratory, Hangzhou 311100, P.R. China
| | - Jie Zheng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, P.R. China
| | - Yiding Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, P.R. China
| | - Frank K Tittel
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, United States
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Pi M, Zheng C, Zhao H, Ji J, Peng Z, Min Y, Huang Y, Wang X, Guan G, Song F, Liang L, Zhang Y, Wang Y, Tittel FK. Mid-infrared auto-correction on-chip waveguide gas sensor based on 2f/1f wavelength modulation spectroscopy. Opt Lett 2024; 49:190-193. [PMID: 38194525 DOI: 10.1364/ol.506008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 11/28/2023] [Indexed: 01/11/2024]
Abstract
Compared to the most commonly used on-chip direct absorption spectroscopy (DAS) gas detection technique, the second harmonic (2f) based on-chip wavelength modulation spectroscopy (WMS) proposed by our group has the faculty to suppress noise and improve performance, but the accuracy of 2f WMS is easily affected by optical power variation. A mid-infrared auto-correction on-chip gas sensor based on 2f/1f WMS was proposed for decreasing the influence of the variation of optical power. The limit of detection of methane (CH4) obtained by a chalcogenide waveguide with a length of 10 mm is 0.031%. Compared with the 2f WMS, the maximum relative concentration error of the auto-correction on-chip gas sensor was decreased by ∼5.6 times. The measurement error is ≤2% in a temperature variation range of 30°C. This auto-correction sensor without a complicated manual calibration is helpful to the high accuracy measurement for on-chip integrated gas sensing.
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Zhao H, Zheng C, Pi M, Liang L, Song F, Zheng K, Zhang Y, Wang Y, Tittel FK. WMS-based near-infrared on-chip acetylene sensor using polymeric SU8 Archimedean spiral waveguide with Euler S-bend. Spectrochim Acta A Mol Biomol Spectrosc 2023; 302:123020. [PMID: 37364413 DOI: 10.1016/j.saa.2023.123020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 06/04/2023] [Accepted: 06/14/2023] [Indexed: 06/28/2023]
Abstract
SU8 is a cost-effective polymer material that is highly suitable for large-scale fabrication of waveguides. However, it has not been employed for on-chip gas measurement utilizing infrared absorption spectroscopy. In this study, we propose a near-infrared on-chip acetylene (C2H2) sensor using SU8 polymer spiral waveguides for the first time to our knowledge. The performance of the sensor based on wavelength modulation spectroscopy (WMS) was experimentally validated. By incorporating the proposed Euler-S bend and Archimedean spiral SU8 waveguide, we achieved a reduction in the sensor's size by over fifty percent. Leveraging the WMS technique, we evaluated the C2H2 sensing performance at 1532.83 nm for SU8 waveguides of lengths 7.4 cm and 13 cm. The limit of detection (LoD) values were 2197.1 ppm (parts per million) and 425.5 ppm, respectively, with an averaging time of 0.2 s. Furthermore, the experimentally obtained optical power confinement factor (PCF) closely approximated the simulated value, with a value of 0.0172 compared to the simulated value of 0.016. The waveguide loss is measured to be 3 dB/cm. The rise time and fall time were approximately 2.05 s and 3.27 s, respectively. This study concludes that the SU8 waveguide exhibits significant potential for high-performance on-chip gas sensing in the near-infrared wavelength range.
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Affiliation(s)
- Huan Zhao
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Chuantao Zheng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China.
| | - Mingquan Pi
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Lei Liang
- State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Fang Song
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Kaiyuan Zheng
- Department of Electrical Engineering and Photonics Research Institute, The Hong Kong Polytechnic University, Hong Kong, China
| | - Yu Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Yiding Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Frank K Tittel
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, TX 77005, USA
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Pi M, Zheng C, Zhao H, Peng Z, Guan G, Ji J, Huang Y, Min Y, Liang L, Song F, Bai X, Zhang Y, Wang Y, Tittel FK. Ultra-Wideband Mid-Infrared Chalcogenide Suspended Nanorib Waveguide Gas Sensors with Exceptionally High External Confinement Factor beyond Free-Space. ACS Nano 2023; 17:17761-17770. [PMID: 37379223 DOI: 10.1021/acsnano.3c02699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
On-chip waveguide sensors are potential candidates for deep-space exploration because of their high integration and low power consumption. Since the fundamental absorption of most gas molecules exists in the mid-infrared (e.g., 3-12 μm), it is of great significance to fabricate wideband mid-infrared sensors with high external confinement factor (ECF). To overcome the limited transparency window and strong waveguide dispersion, a chalcogenide suspended nanorib waveguide sensor was proposed for ultra-wideband mid-infrared gas sensing, and three waveguide sensors (WG1-WG3) with optimized dimensions exhibit a wide waveband of 3.2-5.6 μm, 5.4-8.2 μm, and 8.1-11.5 μm with exceptionally high ECFs of 107-116%, 107-116%, and 116-128%, respectively. The waveguide sensors were fabricated by a two-step lift-off method without dry etching to reduce the process complexity. Experimental ECFs of 112%, 110%, and 110% were obtained at 3.291 μm, 4.319 μm, and 7.625 μm, respectively, through methane (CH4) and carbon dioxide (CO2) measurements. A limit of detection of 5.9 ppm was achieved for an averaging time of 64.2 s through the Allan deviation analysis of CH4 at 3.291 μm, leading to a comparable noise equivalent absorption sensitivity of 2.3 × 10-5 cm-1 Hz-1/2 as compared to the hollow-core fiber and on-chip gas sensors.
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Affiliation(s)
- Mingquan Pi
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Chuantao Zheng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Huan Zhao
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Zihang Peng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Gangyun Guan
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Jialin Ji
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Yijun Huang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Yuting Min
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Lei Liang
- State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Fang Song
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Xue Bai
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Yu Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Yiding Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Frank K Tittel
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, United States
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Zhao H, Zheng C, Pi M, Liang L, Song F, Zhang Y, Wang Y, Tittel FK. On-chip mid-infrared silicon-on-insulator waveguide methane sensor using two measurement schemes at 3.291 μm. Front Chem 2022; 10:953684. [PMID: 36082199 PMCID: PMC9445134 DOI: 10.3389/fchem.2022.953684] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 07/29/2022] [Indexed: 11/18/2022] Open
Abstract
Portable or even on-chip detection of methane (CH4) is significant for environmental protection and production safety. However, optical sensing systems are usually based on discrete optical elements, which makes them unsuitable for the occasions with high portability requirement. In this work, we report on-chip silicon-on-insulator (SOI) waveguide CH4 sensors at 3.291 μm based on two measurement schemes including direct absorption spectroscopy (DAS) and wavelength modulation spectroscopy (WMS). In order to suppress noise, Kalman filter was adopted in signal processing. By optimizing the waveguide cross-section structure, an etch depth of 220 nm was selected with an experimentally high power confinement factor (PCF) of 23% and a low loss of only 0.71 dB/cm. A limit of detection (LoD) of 155 parts-per-million (ppm) by DAS and 78 ppm by WMS at an averaging time of 0.2 s were obtained for a 2 cm-long waveguide sensor. Compared to the chalcogenide (ChG) waveguide CH4 sensors at the same wavelength, the reported sensor reveals the minimum waveguide loss and the lowest LoD. Therefore the SOI waveguide sensor has the potential of on-chip gas sensing in the mid-infrared (MIR) waveband.
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Affiliation(s)
- Huan Zhao
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, China
| | - Chuantao Zheng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, China
- *Correspondence: Chuantao Zheng, ; Lei Liang,
| | - Mingquan Pi
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, China
| | - Lei Liang
- State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, China
- *Correspondence: Chuantao Zheng, ; Lei Liang,
| | - Fang Song
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, China
| | - Yu Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, China
| | - Yiding Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun, China
| | - Frank K. Tittel
- Department of Electrical and Computer Engineering, Rice University, Houston, TX, United States
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Pi M, Zheng C, Zhao H, Peng Z, Lang J, Ji J, Liang L, Zhang Y, Wang Y, Tittel FK. Mid-infrared ChG-on-MgF 2 waveguide gas sensor based on wavelength modulation spectroscopy: publisher's note. Opt Lett 2021; 46:5376. [PMID: 34724479 DOI: 10.1364/ol.445577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Indexed: 06/13/2023]
Abstract
This publisher's note contains corrections to Opt. Lett.46, 4797 (2021)OPLEDP0146-959210.1364/OL.440361.
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Pi M, Zheng C, Zhao H, Peng Z, Lang J, Ji J, Liang L, Zhang Y, Wang Y, Tittel FK. Mid-infrared ChG-on-MgF 2 waveguide gas sensor based on wavelength modulation spectroscopy. Opt Lett 2021; 46:4797-4800. [PMID: 34598202 DOI: 10.1364/ol.440361] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 09/02/2021] [Indexed: 06/13/2023]
Abstract
A novel, to the best of our knowledge, mid-infrared chalcogenide (ChG) on magnesium fluoride (MgF2) waveguide gas sensor was fabricated by using the lift-off method. MgF2 was used as a lower cladding layer to increase the external confinement factor for enhancing light-gas interaction. Wavelength modulation spectroscopy (WMS) was used in carbon dioxide (CO2) detection at the wavelength of 4319 nm (2315.2cm-1). The limit of detection for the 1-cm-long sensing waveguide based on WMS is ∼0.3%, which is >8 times lower than the same sensor using direct absorption spectroscopy (DAS). The combination of WMS with the waveguide gas sensor provides a new measurement scheme for the performance improvement of on-chip gas detection.
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Pi M, Zheng C, Ji J, Zhao H, Peng Z, Lang J, Liang L, Zhang Y, Wang Y, Tittel FK. Surface-Enhanced Infrared Absorption Spectroscopic Chalcogenide Waveguide Sensor Using a Silver Island Film. ACS Appl Mater Interfaces 2021; 13:32555-32563. [PMID: 34185988 DOI: 10.1021/acsami.1c08177] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A surface-enhanced infrared absorption spectroscopic chalcogenide waveguide sensor based on the silver island film was proposed for the first time to enhance the sensing performance in both liquid and gas phases. The chalcogenide waveguide sensor was fabricated by the lift-off and oblique angle deposition methods. The surface morphology of the silver island film with different thicknesses was characterized. The absorption of ethanol (liquid) at a wavelength of 1654 nm and that of methane (gas) at 3291 nm were measured using the fabricated chalcogenide waveguide sensor. The chalcogenide waveguide sensor integrated with the 1.8 nm-thick silver island film revealed the best sensing performance. With an acceptable increased waveguide loss resulting from the fabrication of the film, the absorbance enhancement factors for ethanol and methane were experimentally obtained to be >1.5 and >2.3, respectively. The 1σ limit of detection of methane for the sensor integrated with the 1.8 nm-thick silver island film was ∼4.11% for an averaging time of 0.2 s. The mathematic relation between the absorbance enhancement factor and the waveguide loss was derived for sensing performance improvement. Also, the proposed rectangular waveguide sensor provides an idea for the design of a sensor-on-a-chip instead of other waveguide sensors with a high requirement of fabrication accuracy, for example, a slot waveguide or a photonic crystal waveguide.
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Affiliation(s)
- Mingquan Pi
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Chuantao Zheng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Jialin Ji
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Huan Zhao
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Zihang Peng
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Jiaming Lang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Lei Liang
- State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
| | - Yu Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Yiding Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012, China
| | - Frank K Tittel
- Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, United States
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Pi M, Zheng C, Peng Z, Zhao H, Lang J, Liang L, Zhang Y, Wang Y, Tittel FK. Theoretical study of microcavity-enhanced absorption spectroscopy for mid-infrared methane detection using a chalcogenide/silica-on-fluoride horizontal slot-waveguide racetrack resonator. Opt Express 2020; 28:21432-21446. [PMID: 32752421 DOI: 10.1364/oe.396177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 06/26/2020] [Indexed: 06/11/2023]
Abstract
The reported chalcogenide (ChG) rectangular waveguide sensors with a small evanescent field need a large waveguide length to obtain an enhanced light-gas interaction effect. To make such sensors compact and improve the light-gas interaction effect, a microcavity-enhanced absorption spectroscopy technique for methane (CH4) detection was proposed using a mid-infrared chalcogenide/silica-on-fluoride horizontal slot-waveguide racetrack resonator. For the horizontal slot waveguide, an equivalent sensor model (ESM) and related formulations were proposed to simplify the analysis of the racetrack resonator sensor model (RRSM), and the ESM was verified through a comparison between the theoretical result of ESM and the simulation result of RRSM based on the finite element method (FEM). Due to the use of a chalcogenide/silica-on-fluoride horizontal slot-waveguide structure, the waveguide parameters were optimized to obtain a high power confinement factor of 44.63% at the wavelength of 3291 nm, which is at least 5 times higher than other ChG rectangular waveguides. The waveguide length is reduced at least 30 times due to the use of the optimized chalcogenide/silica-on-fluoride horizontal slot-waveguide and racetrack resonator. The limit of detection (LoD) is 3.87 ppm with an intrinsic waveguide loss of 3 dB/cm and an amplitude coupling ratio of 0.1 for the resonator. The response time is less than 5 µs due to the small light-gas interaction area. The influences of environmental pressure and waveguide intrinsic loss on the sensing characteristics were discussed. The compact racetrack resonator sensor structure and equivalent analytical model can also be adopted in the design of an on-chip waveguide sensor for the detection of other gas species.
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Mudrich M, LaForge AC, Ciavardini A, O'Keeffe P, Callegari C, Coreno M, Demidovich A, Devetta M, Fraia MD, Drabbels M, Finetti P, Gessner O, Grazioli C, Hernando A, Neumark DM, Ovcharenko Y, Piseri P, Plekan O, Prince KC, Richter R, Ziemkiewicz MP, Möller T, Eloranta J, Pi M, Barranco M, Stienkemeier F. Ultrafast relaxation of photoexcited superfluid He nanodroplets. Nat Commun 2020; 11:112. [PMID: 31913265 PMCID: PMC6949273 DOI: 10.1038/s41467-019-13681-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2019] [Accepted: 11/19/2019] [Indexed: 11/23/2022] Open
Abstract
The relaxation of photoexcited nanosystems is a fundamental process of light–matter interaction. Depending on the couplings of the internal degrees of freedom, relaxation can be ultrafast, converting electronic energy in a few fs, or slow, if the energy is trapped in a metastable state that decouples from its environment. Here, we study helium nanodroplets excited resonantly by femtosecond extreme-ultraviolet (XUV) pulses from a seeded free-electron laser. Despite their superfluid nature, we find that helium nanodroplets in the lowest electronically excited states undergo ultrafast relaxation. By comparing experimental photoelectron spectra with time-dependent density functional theory simulations, we unravel the full relaxation pathway: Following an ultrafast interband transition, a void nanometer-sized bubble forms around the localized excitation (He\documentclass[12pt]{minimal}
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\begin{document}$${}^{* }$$\end{document}* at the droplet surface. This study highlights the high level of detail achievable in probing the photodynamics of nanosystems using tunable XUV pulses. There is interest in understanding the relaxation mechanisms of photoexcitation in atoms, molecules and other complex systems. Here the authors unravel the photoexcitation and ultrafast relaxation of superfluid helium nanodroplets using a pump-probe experiment with FEL pulses.
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Affiliation(s)
- M Mudrich
- Department of Physics and Astronomy, Aarhus University, Aarhus C, 8000, Denmark.
| | - A C LaForge
- Institute of Physics, University of Freiburg, Freiburg im Breisgau, 79104, Germany.,Department of Physics, University of Connecticut, Storrs, CT, 06269, USA
| | - A Ciavardini
- CNR-ISM, Area della Ricerca di Roma 1, Monterotondo Scalo, 00015, Italy.,CERIC-ERIC Basovizza, Trieste, 34149, Italy
| | - P O'Keeffe
- CNR-ISM, Area della Ricerca di Roma 1, Monterotondo Scalo, 00015, Italy
| | - C Callegari
- Elettra - Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, 34149, Italy
| | - M Coreno
- CNR-ISM, Area della Ricerca di Roma 1, Monterotondo Scalo, 00015, Italy
| | - A Demidovich
- Elettra - Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, 34149, Italy
| | - M Devetta
- Dipartimento di Fisica, Università degli Studi di Milano, Milan, 20133, Italy.,CNR-IFN, Milano, 20133, Italy
| | - M Di Fraia
- Elettra - Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, 34149, Italy
| | - M Drabbels
- Laboratory of Molecular Nanodynamics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, 1015, Switzerland
| | - P Finetti
- Elettra - Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, 34149, Italy
| | - O Gessner
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - C Grazioli
- CNR-IOM, Istituto Officina dei Materiali, Area Science Park - Basovizza, Trieste, 34149, Italy
| | - A Hernando
- Kido Dynamics, EPFL Innovation Park Bat. C, 1015, Lausanne, Switzerland.,IFISC (CSIC-UIB), Instituto de Fisica Interdisciplinar y Sistemas Complejos, Campus Universitat de les Illes Balears, 07122, Palma de Mallorca, Spain
| | - D M Neumark
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.,Department of Chemistry, University of California, Berkeley, CA, 94720, USA
| | - Y Ovcharenko
- Institut für Optik und Atomare Physik, TU-Berlin, 10623, Germany.,European XFEL, Schenefeld, 22869, Germany
| | - P Piseri
- Dipartimento di Fisica, Università degli Studi di Milano, Milan, 20133, Italy
| | - O Plekan
- Elettra - Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, 34149, Italy
| | - K C Prince
- Elettra - Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, 34149, Italy
| | - R Richter
- Elettra - Sincrotrone Trieste S.C.p.A., Basovizza, Trieste, 34149, Italy
| | - M P Ziemkiewicz
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.,Department of Chemistry, University of California, Berkeley, CA, 94720, USA
| | - T Möller
- Institut für Optik und Atomare Physik, TU-Berlin, 10623, Germany
| | - J Eloranta
- Department of Chemistry and Biochemistry, California State University at Northridge, Northridge, CA, 91330, USA
| | - M Pi
- Departament FQA, Facultat de Física, Universitat de Barcelona, Barcelona, 08028, Spain.,Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, 08028, Spain
| | - M Barranco
- Departament FQA, Facultat de Física, Universitat de Barcelona, Barcelona, 08028, Spain.,Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, 08028, Spain.,Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, UMR 5589, CNRS et Université Paul Sabatier-Toulouse 3, Toulouse, Cedex 09, 31062, France
| | - F Stienkemeier
- Institute of Physics, University of Freiburg, Freiburg im Breisgau, 79104, Germany
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12
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von Vangerow J, Sieg A, Stienkemeier F, Mudrich M, Leal A, Mateo D, Hernando A, Barranco M, Pi M. Desorption Dynamics of Heavy Alkali Metal Atoms (Rb, Cs) Off the Surface of Helium Nanodroplets. J Phys Chem A 2014; 118:6604-14. [DOI: 10.1021/jp503308w] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J. von Vangerow
- Physikalisches
Institut, Universität Freiburg, 79104 Freiburg, Germany
| | - A. Sieg
- Physikalisches
Institut, Universität Freiburg, 79104 Freiburg, Germany
| | - F. Stienkemeier
- Physikalisches
Institut, Universität Freiburg, 79104 Freiburg, Germany
| | - M. Mudrich
- Physikalisches
Institut, Universität Freiburg, 79104 Freiburg, Germany
| | - A. Leal
- Departament
ECM, Facultat de Física and IN2UB, Universitat de Barcelona, 08028 Barcelona, Spain
| | - D. Mateo
- Departament
ECM, Facultat de Física and IN2UB, Universitat de Barcelona, 08028 Barcelona, Spain
- Department
of Chemistry and Biochemistry, California State University at Northridge, 18111 Nordhoff Street, Northridge, California 91330, United States
| | - A. Hernando
- Laboratoire
de Chimie Physique Moléculaire, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - M. Barranco
- Departament
ECM, Facultat de Física and IN2UB, Universitat de Barcelona, 08028 Barcelona, Spain
| | - M. Pi
- Departament
ECM, Facultat de Física and IN2UB, Universitat de Barcelona, 08028 Barcelona, Spain
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Abstract
A finite-temperature density functional approach to describe the properties of parahydrogen in the liquid-vapor coexistence region is presented. The first proposed functional is zero-range, where the density-gradient term is adjusted so as to reproduce the surface tension of the liquid-vapor interface at low temperature. The second functional is finite-range and, while it is fitted to reproduce bulk pH(2) properties only, it is shown to yield surface properties in good agreement with experiments. These functionals are used to study the surface thickness of the liquid-vapor interface, the wetting transition of parahydrogen on a planar Rb model surface, and homogeneous cavitation in bulk liquid pH(2).
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Affiliation(s)
- J Navarro
- IFIC (CSIC and Universidad de Valencia), Apdo. 22085, 46071 Valencia, Spain
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14
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Affiliation(s)
- F. Ancilotto
- INFM-CNR DEMOCRITOS National Simulation Center and Dipartimento di Fisica “G. Galilei”, Università di Padova, via Marzolo 8, I-35131 Padova, Italy, Departament ECM, Facultat de Física, and IN2UB, Universitat de Barcelona. Diagonal 647, 08028 Barcelona, Spain, and Departament of Chemistry and Physics, University of Virginia, 22904-4319 Charlottesville, Virginia
| | - M. Pi
- INFM-CNR DEMOCRITOS National Simulation Center and Dipartimento di Fisica “G. Galilei”, Università di Padova, via Marzolo 8, I-35131 Padova, Italy, Departament ECM, Facultat de Física, and IN2UB, Universitat de Barcelona. Diagonal 647, 08028 Barcelona, Spain, and Departament of Chemistry and Physics, University of Virginia, 22904-4319 Charlottesville, Virginia
| | - R. Mayol
- INFM-CNR DEMOCRITOS National Simulation Center and Dipartimento di Fisica “G. Galilei”, Università di Padova, via Marzolo 8, I-35131 Padova, Italy, Departament ECM, Facultat de Física, and IN2UB, Universitat de Barcelona. Diagonal 647, 08028 Barcelona, Spain, and Departament of Chemistry and Physics, University of Virginia, 22904-4319 Charlottesville, Virginia
| | - M. Barranco
- INFM-CNR DEMOCRITOS National Simulation Center and Dipartimento di Fisica “G. Galilei”, Università di Padova, via Marzolo 8, I-35131 Padova, Italy, Departament ECM, Facultat de Física, and IN2UB, Universitat de Barcelona. Diagonal 647, 08028 Barcelona, Spain, and Departament of Chemistry and Physics, University of Virginia, 22904-4319 Charlottesville, Virginia
| | - K. K. Lehmann
- INFM-CNR DEMOCRITOS National Simulation Center and Dipartimento di Fisica “G. Galilei”, Università di Padova, via Marzolo 8, I-35131 Padova, Italy, Departament ECM, Facultat de Física, and IN2UB, Universitat de Barcelona. Diagonal 647, 08028 Barcelona, Spain, and Departament of Chemistry and Physics, University of Virginia, 22904-4319 Charlottesville, Virginia
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15
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Mayol R, Barranco M, Hernández ES, Pi M, Guilleumas M. Bound states of 3He at the edge of a 4He drop on a cesium surface. Phys Rev Lett 2003; 90:185301. [PMID: 12786017 DOI: 10.1103/physrevlett.90.185301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2002] [Indexed: 05/24/2023]
Abstract
We show that small amounts of 3He atoms, added to a 4He drop deposited on a flat cesium surface at zero temperature, populate bound states localized at the contact line. These edge states show up for drops large enough to develop well defined surface and bulk regions together with a contact line, and they are structurally different from the well-known Andreev states that appear at the free surface and at the liquid-solid interface of films. We illustrate the one-body density of 3He in a drop with 1000 4He atoms, and show that for a sufficiently large number of impurities the density profiles spread beyond the edge, coating both the curved drop surface and its flat base and eventually isolating it from the substrate.
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Affiliation(s)
- R Mayol
- Departament ECM, Facultat de Física, Universitat de Barcelona, E-08028 Barcelona, Spain
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16
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Abstract
Using density functional theory, we investigate the structure of mixed (3)He(N3)-(4)He(N4) droplets with an embedded impurity (Xe atom or HCN molecule) which pins a quantized vortex line. We find that the dopant+vortex+(4)He(N4) complex, which in a previous work [F. Dalfovo et al., Phys. Rev. Lett. 85, 1028 (2000)] was found to be energetically stable below a critical size N(cr), is robust against the addition of 3He. While 3He atoms are distributed along the vortex line and on the surface of the 4He drop, the impurity is mostly coated by 4He atoms. Results for N4 = 500 and a number of 3He atoms ranging from 0 to 100 are presented, and the binding energy of the dopant to the vortex line is determined.
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Affiliation(s)
- R Mayol
- Departament ECM, Facultat de Física, Universitat de Barcelona, E-08028 Barcelona, Spain
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17
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Abstract
The hypothesis that local changes in extracellular calcium may serve a physiological role in regulating osteoblast, osteoclast, and cartilage function through the extracellular cation-sensing receptor, CasR, is gaining widespread support, but lacks definite proof. To examine the effects of CasR deficiency on the skeleton, we performed a detailed analysis of the skeleton in CasR knockout mice (CasR(-/-)) and wild-type littermates (CasR(+/+)). CasR ablation in the parathyroid glands of CasR(-/-) mice resulted in hyperparathyroidism, hypercalcemia, and hypophosphatemia. Except for dwarfism, the expected skeletal manifestations of PTH excess, namely chondrodysplasia and increased mineralized bone formation and resorption, were not the main skeletal features in CasR(-/-) mice. Rather, rickets was the predominant skeletal abnormality in these animals, as evidenced by a widened zone of hypertrophic chondrocytes, impaired growth plate calcification and disorderly deposition of mineral, excessive osteoid accumulation, and prolonged mineralization lag time in metaphyseal bone. CasR transcripts were identified in cartilage and bone marrow of CasR(+/+) mice, but not in mineralized bone containing mature osteoblasts and osteocytes. These findings indicate that a calcium-sensing receptor is present in the skeleton, and its absence results in defective mineralization of cartilage and bone by mechanisms that remain to be elucidated.
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Affiliation(s)
- S C Garner
- Division of Nephrology, Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA
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18
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Pi M, Emperador A, Barranco M, Garcias F, Muraki K, Tarucha S, Austing DG. Dissociation of vertical semiconductor diatomic artificial molecules. Phys Rev Lett 2001; 87:066801. [PMID: 11497840 DOI: 10.1103/physrevlett.87.066801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2001] [Indexed: 05/23/2023]
Abstract
We investigate the dissociation of few-electron circular vertical semiconductor double quantum dot artificial molecules at 0 T as a function of interdot distance. A slight mismatch introduced in the fabrication of the artificial molecules from nominally identical constituent quantum wells induces localization by offsetting the energy levels in the quantum dots by up to 2 meV, and this plays a crucial role in the appearance of the addition energy spectra as a function of coupling strength particularly in the weak coupling limit.
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Affiliation(s)
- M Pi
- Departament ECM, Facultat de Física, Universitat de Barcelona, E-08028 Barcelona, Spain
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19
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Abstract
This paper presents a new adaptive search approach to reduce the computational complexity of fractal encoding. A simple but very efficient adaptive necessary condition is introduced to exclude a large number of unqualified domain blocks so as to speed-up fractal image compression. Furthermore, we analyzed an unconventional affine parameter that has better properties than the conventional luminance offset. Specifically, we formulated an optimal bit allocation scheme for the simultaneous quantizations of the usual scaling and the aforementioned unconventional affine parameter. Experiments on standard images showed that our adaptive search method yields superior performance over conventional fractal encoding.
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Affiliation(s)
- C S Tong
- Dept. of Math., Hong Kong Baptist Univ.
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20
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Dalfovo F, Mayol R, Pi M, Barranco M. Pinning of quantized vortices in helium drops by dopant atoms and molecules. Phys Rev Lett 2000; 85:1028-1031. [PMID: 10991466 DOI: 10.1103/physrevlett.85.1028] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/1999] [Indexed: 05/23/2023]
Abstract
Using a density functional method, we investigate the properties of liquid 4He droplets doped with atoms (Ne and Xe) and molecules ( SF6 and hydrogen cyanide). We consider the case of droplets having a quantized vortex pinned to the dopant. A liquid-drop formula is proposed that accurately describes the total energy of the complex and allows one to extrapolate the density functional results to large N. For a given impurity, we find that the formation of a dopant+vortex+(4)He(N) complex is energetically favored below a critical size N(cr). Our results support the possibility to observe quantized vortices in helium droplets by means of spectroscopic techniques.
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Affiliation(s)
- F Dalfovo
- Dipartimento di Matematica e Fisica, Universita Cattolica, Via Musei 41, I-25121 Brescia, Italy and and Istituto Nazionale per la Fisica della Materia, Unita di Trento, I-38050 Povo, Italy
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21
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Ogawa S, Yoshino R, Angata K, Iwamoto M, Pi M, Kuroe K, Matsuo K, Morio T, Urushihara H, Yanagisawa K, Tanaka Y. The mitochondrial DNA of Dictyostelium discoideum: complete sequence, gene content and genome organization. Mol Gen Genet 2000; 263:514-9. [PMID: 10821186 DOI: 10.1007/pl00008685] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We present an overview of the gene content and organization of the mitochondrial genome of Dictyostelium discoideum. The mitochondria genome consists of 55,564 bp with an A + T content of 72.6%. The identified genes include those for two ribosomal RNAs (rn1 and rns), 18 tRNAs, ten subunits of the NADH dehydrogenase complex (nad1, 2, 3, 4, 4L, 5, 6, 7, 9 and 11), apocytochrome b (cytb), three subunits of the cytochrome oxidase (cox1/2 and 3), four subunits of the ATP synthase complex (atp1, 6, 8 and 9), 15 ribosomal proteins, and five other ORFs, excluding intronic ORFs. Notable features of D. discoideum mtDNA include the following. (1) All genes are encoded on the same strand of the DNA and a universal genetic code is used. (2) The cox1 gene has no termination codon and is fused to the downstream cox2 gene. The 13 genes for ribosomal proteins and four ORF genes form a cluster 15.4 kb long with several gene overlaps. (3) The number of tRNAs encoded in the genome is not sufficient to support the synthesis of mitochondrial protein. (4) In total, five group I introns reside in rnl and cox1/2, and three of those in cox1/2 contain four free-standing ORFs. We compare the genome to other sequenced mitochondrial genomes, particularly that of Acanthamoeba castellanii.
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Affiliation(s)
- S Ogawa
- Institute of Biological Sciences, Ibaraki, Japan
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22
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Pi M, Garner SC, Flannery P, Spurney RF, Quarles LD. Sensing of extracellular cations in CasR-deficient osteoblasts. Evidence for a novel cation-sensing mechanism. J Biol Chem 2000; 275:3256-63. [PMID: 10652312 DOI: 10.1074/jbc.275.5.3256] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We isolated osteoblastic cell lines from wild-type (CasR(+/+)) and receptor null (CasR(-/-)) mice to investigate whether CasR is present in osteoblasts and accounts for their responses to extracellular cations. Osteoblasts from both CasR(+/+) and CasR(-/-) mice displayed an initial period of cell replication followed by a culture duration-dependent increase in alkaline phosphatase activity, expression of osteocalcin, and mineralization of extracellular matrix. In addition, a panel of extracellular cations, including aluminum and the CasR agonists gadolinium and calcium, stimulated DNA synthesis, activated a transfected serum response element-luciferase reporter construct, and inhibited agonist-induced cAMP in CasR(-/-) osteoblasts. The functional responses to these cations were identical in CasR(+/+) and CasR(-/-) osteoblasts. Thus, the absence of CasR alters neither the maturational profile of isolated osteoblast cultures nor their in vitro responses to extracellular cations. In addition, CasR transcripts could not be detected by reverse transcription-polymerase chain reaction with mouse specific primers in either CasR(+/+) or CasR(-/-) osteoblasts, and immunoblot analysis with a CasR-specific antibody was negative for CasR protein expression in osteoblasts. The presence of a cation-sensing response in osteoblasts from CasR(-/-) mice indicates the existence of a novel osteoblastic extracellular cation-sensing mechanism.
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Affiliation(s)
- M Pi
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA
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Abstract
Whether the known calcium-sensing receptor (CasR) is present in osteoblasts is a source of considerable controversy. Prior studies failed to detect CasR in osteoblasts, but more recent investigations purport the detection of CasR in several osteoblast cell lines by immunoblot analysis with polyclonal anti-CasR antisera (4637) and low stringency reverse transcriptase-polymerase chain reaction (RT-PCR). To explain these disparate findings, we performed immunoblot analysis with the 4637 anti-CasR antisera and a highly specific monoclonal antibody to CasR (ADD), and we compared the ability of low and high stringency RT-PCR to amplify CasR transcripts. We found that the ADD antibody detected the anticipated CasR immunoreactive bands, including a approximately 165 kDa and approximately 140 kDa glycosylated doublet and a >250 kDa dimerized receptor, in positive control mouse kidney, human parathyroid, and human embryonic kidney (HEK) 293 cells transfected with rat CasR, but we did not detect these bands in either wild-type HEK 293 cells or Saos2, MG-63, or U-2 OS osteoblast-like cell lines. Standard two-step RT-PCR using CasR-specific primers confirmed these results by detecting CasR transcripts in positive controls but not in negative control HEK 293 cells or osteoblast cell lines. In contrast, the 4637 antisera did not recognize CasR by immunoblot analysis under the conditions studied and our low stringency RT-PCR procedure amplified nonspecific products in wild-type HEK 293 cells and osteoblasts. Since we failed to detect CasR in human osteoblast cell lines using either the highly specific ADD antibody or RT-PCR under standard conditions, it is possible that the cation response in osteoblasts is mediated by a functionally similar but molecularly distinct calcium sensing receptor.
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Affiliation(s)
- M Pi
- Duke University Medical Center, Durham, North Carolina 27710, USA
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Abstract
BACKGROUND Aluminum (Al3+) has diverse biological effects mediated through activation of a putative extracellular cation-sensing receptor. A recently identified calcium-sensing receptor (CaSR), which has been identified in target tissues for Al3+, may transduce some of the biological effects of Al3+. METHODS To test this possibility, we transfected human embryonic kidney 293 (HEK 293) cells with a cDNA encoding the rat CaSR and evaluated CaSR expression by Western blot analysis and function by measurement of intracellular calcium ([Ca2+]i) levels and inositol monophosphate (IP1) generation following stimulation with Al3+ and a panel of CaSR agonists. RESULTS The CaSR protein was detected by immunoblot analysis in cells transfected with the CaSR cDNA but not in nontransfected HEK 293 cells. In addition, [Ca2+]i levels and IP1 generation were enhanced in a dose-dependent fashion by additions of the CaSR agonists calcium (Ca2+), magnesium (Mg2+), gadolinium (Gd3+), and neomycin only in cells transfected with CaSR. To determine if Al3+ activated CaSR, we stimulated cells transfected with rat CaSR with 10 microM to 1 mM concentrations of Al3+. Concentrations of Al3+ in the range of 10 microM to 100 microM had no effect on [Ca2+]i levels or IP1 generation. In contrast, 1 mM Al3+ induced small but significant increases in both parameters. Whereas Gd3+ antagonized calcium-mediated activation of CaSR, pretreatment with Al3+ failed to block subsequent activation of rat CaSR by Ca2+, suggesting a distinct mechanism of Al3+ action. CONCLUSION Al3+ is not a potent agonist for CaSR. Because Al3+ affects a variety of target tissues at micromolar concentrations, it seems unlikely that CaSR mediates these cellular actions of Al3+.
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Affiliation(s)
- R F Spurney
- Duke University Medical Center, Durham, North Carolina, USA
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Morio T, Urushihara H, Saito T, Ugawa Y, Mizuno H, Yoshida M, Yoshino R, Mitra BN, Pi M, Sato T, Takemoto K, Yasukawa H, Williams J, Maeda M, Takeuchi I, Ochiai H, Tanaka Y. The Dictyostelium developmental cDNA project: generation and analysis of expressed sequence tags from the first-finger stage of development. DNA Res 1998; 5:335-40. [PMID: 10048482 DOI: 10.1093/dnares/5.6.335] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In an effort to identify and characterize genes expressed during multicellular development ill Dictyostelium, we have undertaken a cDNA sequencing project. Using size-fractionated subsets of cDNA from the first finger stage, two sets of gridded libraries were constructed for cDNA sequencing. One, library S, consisting of 9984 clones, carries relatively short inserts, and the other, library L, which consists of 8448 clones, has longer inserts. We sequenced all the selected clones in library S from their 3'-ends, and this generated 3093 non-redundant, expressed sequence tags (ESTs). Among them, 246 ESTs hit known Dictyostelium genes and 910 showed significant similarity to genes of Dictyostelium and other organisms. For library L, 1132 clones were randomly sequenced and 471 non-redundant ESTs were obtained. In combination, the ESTs from the two libraries represent approximately 40% of genes expressed in late development, assuming that the non-redundant ESTs correspond to independent genes. They will provide a useful resource for investigating the genetic networks that regulate multicellular development of this organism.
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Affiliation(s)
- T Morio
- Institute of Biological Sciences, Univ., Tsukuba, Ibaraki, Japan
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Iwamoto M, Pi M, Kurihara M, Morio T, Tanaka Y. A ribosomal protein gene cluster is encoded in the mitochondrial DNA of Dictyostelium discoideum: UGA termination codons and similarity of gene order to Acanthamoeba castellanii. Curr Genet 1998; 33:304-10. [PMID: 9560439 DOI: 10.1007/s002940050341] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We sequenced a region of about 14.5 kb downstream from the ribosomal protein L11 gene (rpl11) in the mitochondrial DNA (54+/-2 kb) of the cellular slime mold Dictyostelium discoideum. Sequence analysis revealed that eleven ribosomal protein genes and six open reading frames (ORFs) formed a cluster arranged in the order: rpl11-orf189-rps12-rps7-rpl2-rps19-+ ++orf425-orf1740-rpl16-rpl14-orf188- rps14-rps8-rpl6-rps13-orf127-orf796. This order was very similar to that of homologous genes in Acanthamoeba castellanii mitochondrial DNA. The N-terminal region of ORF425 and the C-terminal region of ORF1740 had partial similarities to the S3 ribosomal protein of other organisms. The termination codons of rpl16 and orf188 were UGA, which has not hitherto been found in genes encoded in D. discoideum mitochondrial DNA.
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Affiliation(s)
- M Iwamoto
- Institute of Biological Sciences, University of Tsukuba, Japan
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28
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Pi M, Morio T, Urushihara H, Tanaka Y. Characterization of a novel small RNA encoded by Dictyostelium discoideum mitochondrial DNA. Mol Gen Genet 1998; 257:124-31. [PMID: 9491070 DOI: 10.1007/s004380050631] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In this study, we analyzed a mitochondrial small (ms) RNA in Dictyostelium discoideum, which is 129 nucleotides long and has a GC content of only 22.5%. In the mitochondrial DNA, a single-copy gene (msr) for the ms RNA was located downstream of the gene for large-subunit rRNA. The location of msr was similar to that of the 5S rRNA gene in prokaryotes and chloroplasts, but clearly different from that in mitochondria of plants, liverwort and the chlorophycean alga Prototheca wikerhamii, in which small-subunit rRNA and 5S rRNA genes are closely linked. THe primary sequence of ms rRNA showed low homology with mitochondrial 5S rRNA from plants, liverwort and the chlorophycean alga, but the proposed secondary structure of ms RNA was similar to that of cytoplasmic 5S rRNA. In addition, ms RNA showed a highly conserved GAAC sequence in the same loop as in common 5S rRNA. However, ms RNA was detected mainly in the mitochondrial 25,000 x g supernatant fraction which was devoid of ribosomes. It is possible that ms RNA is an evolutionary derivative of mitochondrial 5S rRNA.
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Affiliation(s)
- M Pi
- Institute of Biological Sciences, University of Tsukuba, Ibaraki, Japan
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Guilleumas M, Barranco M, Jezek DM, Lombard RJ, Pi M. Quantum cavitation in liquid helium. Phys Rev B Condens Matter 1996; 54:16135-16138. [PMID: 9985689 DOI: 10.1103/physrevb.54.16135] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Guilleumas M, Pi M, Barranco M, Jezek DM, Navarro J. Nucleation in supersaturated solutions of 3He in 4He at negative pressures. Phys Rev B Condens Matter 1995; 52:1210-1214. [PMID: 9980701 DOI: 10.1103/physrevb.52.1210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Jezek DM, Guilleumas M, Pi M, Barranco M. Critical supersaturation of 3He-4He liquid mixtures at low temperatures. Phys Rev B Condens Matter 1995; 51:11981-11983. [PMID: 9977949 DOI: 10.1103/physrevb.51.11981] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Barberán N, Pi M. Static polarizability associated with multipole surface plasmons in metallic surfaces. Phys Rev B Condens Matter 1995; 51:7329-7332. [PMID: 9977305 DOI: 10.1103/physrevb.51.7329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Guilleumas M, Jezek DM, Pi M, Barranco M, Navarro J. Cavitation in 3He-4He liquid mixtures at low temperatures. Phys Rev B Condens Matter 1995; 51:1140-1146. [PMID: 9978268 DOI: 10.1103/physrevb.51.1140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Jezek DM, Guilleumas M, Pi M, Barranco M, Navarro J. Thermal nucleation and cavitation in 3He and 4He. Phys Rev B Condens Matter 1993; 48:16582-16588. [PMID: 10008242 DOI: 10.1103/physrevb.48.16582] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Guilleumas M, Pi M, Barranco M, Navarro J, Solís MA. Thermal nucleation of cavities in liquid helium at negative pressures. Phys Rev B Condens Matter 1993; 47:9116-9119. [PMID: 10004968 DOI: 10.1103/physrevb.47.9116] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Abstract
Wave-front matching of the local oscillator beam and the signal beam is of vital importance in optical heterodyne efficiency. A method for aligning the local oscillator beam and the signal beam is described. Mixing efficiency is improved. One can directly observe the matching procedure on an oscilloscope.
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Serra L, Garcías F, Navarro J, Barberán N, Barranco M, Pi M. Electronic surface excitations of cavities in metals. Phys Rev B Condens Matter 1992; 46:9369-9379. [PMID: 10002741 DOI: 10.1103/physrevb.46.9369] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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