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Chiappim W, Testoni G, Miranda F, Fraga M, Furlan H, Saravia DA, Sobrinho ADS, Petraconi G, Maciel H, Pessoa R. Effect of Plasma-Enhanced Atomic Layer Deposition on Oxygen Overabundance and Its Influence on the Morphological, Optical, Structural, and Mechanical Properties of Al-Doped TiO 2 Coating. MICROMACHINES 2021; 12:mi12060588. [PMID: 34063804 PMCID: PMC8223979 DOI: 10.3390/mi12060588] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 05/19/2021] [Indexed: 11/16/2022]
Abstract
The chemical, structural, morphological, and optical properties of Al-doped TiO2 thin films, called TiO2/Al2O3 nanolaminates, grown by plasma-enhanced atomic layer deposition (PEALD) on p-type Si <100> and commercial SLG glass were discussed. High-quality PEALD TiO2/Al2O3 nanolaminates were produced in the amorphous and crystalline phases. All crystalline nanolaminates have an overabundance of oxygen, while amorphous ones lack oxygen. The superabundance of oxygen on the crystalline film surface was illustrated by a schematic representation that described this phenomenon observed for PEALD TiO2/Al2O3 nanolaminates. The transition from crystalline to amorphous phase increased the surface hardness and the optical gap and decreased the refractive index. Therefore, the doping effect of TiO2 by the insertion of Al2O3 monolayers showed that it is possible to adjust different parameters of the thin-film material and to control, for example, the mobility of the hole-electron pair in the metal-insulator-devices semiconductors, corrosion protection, and optical properties, which are crucial for application in a wide range of technological areas, such as those used to manufacture fluorescence biosensors, photodetectors, and solar cells, among other devices.
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Affiliation(s)
- William Chiappim
- Laboratório de Plasmas e Processos, Instituto Tecnológico de Aeronáutica, Praça Marechal Eduardo Gomes 50, São José dos Campos 12228-900, Brazil; (G.T.); (F.M.); (A.d.S.S.); (G.P.); (H.M.)
- i3N, Departamento de Física, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
- Correspondence: (W.C.); (M.F.); (R.P.); Tel.: +55-12-3947-5785 (R.P.)
| | - Giorgio Testoni
- Laboratório de Plasmas e Processos, Instituto Tecnológico de Aeronáutica, Praça Marechal Eduardo Gomes 50, São José dos Campos 12228-900, Brazil; (G.T.); (F.M.); (A.d.S.S.); (G.P.); (H.M.)
| | - Felipe Miranda
- Laboratório de Plasmas e Processos, Instituto Tecnológico de Aeronáutica, Praça Marechal Eduardo Gomes 50, São José dos Campos 12228-900, Brazil; (G.T.); (F.M.); (A.d.S.S.); (G.P.); (H.M.)
| | - Mariana Fraga
- Instituto de Ciência e Tecnologia, Universidade Federal de São Paulo, Rua Talim 330, São José dos Campos 12231-280, Brazil
- Correspondence: (W.C.); (M.F.); (R.P.); Tel.: +55-12-3947-5785 (R.P.)
| | - Humber Furlan
- Centro Estadual de Educação Tecnológica Paula Souza, Programa de Pós-Graduação em Gestão e Tecnologia em Sistemas Produtivos, São Paulo 01124-010, Brazil;
| | | | - Argemiro da Silva Sobrinho
- Laboratório de Plasmas e Processos, Instituto Tecnológico de Aeronáutica, Praça Marechal Eduardo Gomes 50, São José dos Campos 12228-900, Brazil; (G.T.); (F.M.); (A.d.S.S.); (G.P.); (H.M.)
| | - Gilberto Petraconi
- Laboratório de Plasmas e Processos, Instituto Tecnológico de Aeronáutica, Praça Marechal Eduardo Gomes 50, São José dos Campos 12228-900, Brazil; (G.T.); (F.M.); (A.d.S.S.); (G.P.); (H.M.)
| | - Homero Maciel
- Laboratório de Plasmas e Processos, Instituto Tecnológico de Aeronáutica, Praça Marechal Eduardo Gomes 50, São José dos Campos 12228-900, Brazil; (G.T.); (F.M.); (A.d.S.S.); (G.P.); (H.M.)
- Instituto Científico e Tecnológico, Universidade Brasil, São Paulo 08230-030, Brazil
| | - Rodrigo Pessoa
- Laboratório de Plasmas e Processos, Instituto Tecnológico de Aeronáutica, Praça Marechal Eduardo Gomes 50, São José dos Campos 12228-900, Brazil; (G.T.); (F.M.); (A.d.S.S.); (G.P.); (H.M.)
- Correspondence: (W.C.); (M.F.); (R.P.); Tel.: +55-12-3947-5785 (R.P.)
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Fu M, Zheng Y, Li G, Hu H, Pu M, Oxenløwe LK, Frandsen LH, Li X, Guan X. High-Q titanium dioxide micro-ring resonators for integrated nonlinear photonics. OPTICS EXPRESS 2020; 28:39084-39092. [PMID: 33379466 DOI: 10.1364/oe.404821] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 12/05/2020] [Indexed: 06/12/2023]
Abstract
We report on the nonlinear characterizations of the titanium dioxide micro-ring resonators (TiO2 MRRs). By utilizing optimized fabrication processes, high quality factors (Q∼1.4 × 105) doubling that of the previous work are achieved here for TiO2 MRRs with high-confinement TiO2 waveguides. The four-wave mixing (FWM) experiment results with low and high signal power demonstrate that, the fabricated TiO2 MRRs can perform broadband (∼40 nm) wavelength conversion and cascaded FWMs. These achievements pave the way for key nonlinear photonic applications with TiO2 waveguides and provide an efficient platform for various integrated photonic devices.
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Graniel O, Weber M, Balme S, Miele P, Bechelany M. Atomic layer deposition for biosensing applications. Biosens Bioelectron 2018; 122:147-159. [DOI: 10.1016/j.bios.2018.09.038] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 09/03/2018] [Accepted: 09/12/2018] [Indexed: 01/02/2023]
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Kunala K, Poutous MK. Diffraction efficiency performance of random anti-reflecting subwavelength surface structures on prefabricated fused silica binary gratings. APPLIED OPTICS 2018; 57:4421-4427. [PMID: 29877388 DOI: 10.1364/ao.57.004421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 05/02/2018] [Indexed: 06/08/2023]
Abstract
Random anti-reflecting subwavelength surface structures have been reported to enhance transmission of optical windows and lenses. Specifically, for fused silica substrates, 99.9% specular transmission has been verified by various groups. Diffractive optical elements, such as gratings, also experience net Fresnel losses on both their planar and structured surfaces. We investigated the performance of prefabricated 50% duty-cycle, binary, fused silica linear gratings, with a period of 1.6 μm, before and after application of random anti-reflecting subwavelength surface structures, in order to reduce their initial Fresnel reflectivity. We compared the diffraction order directions and their efficiencies at three test wavelengths: 594, 612, and 633 nm, for both TE(s) and TM(p) incident light polarization states, under three different mountings: normal, first Bragg, and second Bragg incidence. We report transmission enhancement of the sum of all propagating grating orders for all cases tested by factors between 2% and 10%, with reduction of the respective reflected orders by similar ratios. Transmission enhancement of the -2 diffraction order at Bragg incidence suggests that the random etch has different rates between the raised and lowered linear grating topography.
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Ahmadi L, Hiltunen M, Hiltunen J, Aikio S, Saarinen J, Honkanen S, Roussey M. Influence of an Al 2O 3 surface coating on the response of polymeric waveguide sensors. OPTICS EXPRESS 2017; 25:25102-25112. [PMID: 29041182 DOI: 10.1364/oe.25.025102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 09/16/2017] [Indexed: 06/07/2023]
Abstract
The responses of a polymer ridge waveguide Young interferometer with and without a bilayer of Al2O3/TiO2, fabricated by atomic layer deposition, are studied and compared when applied as an aqueous chemical sensor. The phase shift of the guided mode, as a result of the change in refractive index of the cover medium, is monitored. The results indicate that the over-coating affects the linearity of the sensor response. The effect of concentration on the linearity of the sensor response is investigated by applying different concentrations of water-ethanol solution. Although the performance of the sensor is improved by the additional layers, the study reveals a non-monotonic behavior of the device. We show that it comes mainly from the adsorption of ethanol molecules on the surface of the films. Such an understanding of the platform is crucial for sensing of analytes involving polar molecules.
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Paul S, Vartiainen I, Roussey M, Saastamoinen T, Tervo J, Honkanen S, Kuittinen M. Add-drop filter based on TiO 2 coated shifted Bragg grating. OPTICS EXPRESS 2016; 24:26901-26910. [PMID: 27857418 DOI: 10.1364/oe.24.026901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We present a titanium dioxide coated shifted Bragg grating in a silicon-on-insulator platform enabling optical add-drop functionality. The device works on the basis of mode conversion due to shifted sidewall structure followed by mode splitting based on an asymmetric Y-coupler. We experimentally demonstrate the working principle of the device. A reflection bandwidth of 2.2 nm with 14 dB extinction ratio is obtained with a 300 μm long shifted Bragg grating. The performance of the device is also compared without the titanium dioxide coating. A scope of spectral tunability with titanium dioxide re-coating (0.8 nm per 1 nm re-coating) by atomic layer deposition is experimentally verified.
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Smietana M, Koba M, Brzozowska E, Krogulski K, Nakonieczny J, Wachnicki L, Mikulic P, Godlewski M, Bock WJ. Label-free sensitivity of long-period gratings enhanced by atomic layer deposited TiO(2) nano-overlays. OPTICS EXPRESS 2015; 23:8441-8453. [PMID: 25968683 DOI: 10.1364/oe.23.008441] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this paper, we discuss an impact of thin titanium dioxide (TiO(2)) coatings on refractive index (RI) sensitivity and biofunctionalization of long-period gratings (LPGs). The TiO(2) overlays on the LPG surfaces have been obtained using atomic layer deposition (ALD) method. This method allows for a deposition of conformal, thickness-controlled, with well-defined optical properties, and high-RI thin films which are highly desired for optical fiber sensors. It has been found that for LPGs working at a dispersion turning point of higher order cladding modes only tens of nanometers of TiO(2) overlay thickness allow to obtain cladding mode transition effect, and thus significant improvement of RI sensitivity. When the TiO(2) overlay thickness reaches 70 nm, it is possible to obtain RI sensitivity exceeding 6200 nm/RIU in RI range where label-free sensors operate. Moreover, LPGs with TiO(2)-enhanced RI sensitivity have shown improved sensitivity to bacteria endotoxin (E. coli B lipopolysaccharide) detection, when TiO(2) surface is functionalized with endotoxin binding protein (adhesin) of T4 bacteriophage.
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Häyrinen M, Roussey M, Säynätjoki A, Kuittinen M, Honkanen S. Titanium dioxide slot waveguides for visible wavelengths. APPLIED OPTICS 2015; 54:2653-2657. [PMID: 25967172 DOI: 10.1364/ao.54.002653] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 02/25/2015] [Indexed: 06/04/2023]
Abstract
We present the first, to our knowledge, experimental demonstration of a titanium dioxide slot waveguide operating in the visible range of light. Ring resonators based on slot waveguides were designed, fabricated, and characterized for λ≃650 nm. The fabrication method includes atomic layer deposition, electron beam lithography, and reactive ion etching. The required narrow slot widths of a few tens of nanometers were achieved by using a conformal atomic layer re-coating technique. This unique feature-size-reduction technique was applied after the final etching step.
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Ahmadi L, Tervo J, Saarinen J, Honkanen S. Enhanced sensitivity in polymer slot waveguides by atomic layer deposited bilayer coatings. APPLIED OPTICS 2013; 52:8089-8094. [PMID: 24513762 DOI: 10.1364/ao.52.008089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 10/21/2013] [Indexed: 06/03/2023]
Abstract
The refractive index sensitivity of a polymer slot waveguide coated with a bilayer of Al₂O₃/TiO₂ was investigated theoretically and optimized for biosensor applications. The influence of atomic-layer-deposition-coated thin high-refractive-index layers on the slot confinement factor and the homogeneous sensitivity of polymer slot waveguides with different geometries were simulated. The results were compared with those of an optimized noncoated polymer slot waveguide, both operating at visible wavelengths. The simulations reveal that the proposed structure offers a significant improvement in the confinement factor and the sensitivity. These calculations present guidelines for the design and fabrication of relatively sensitive polymer slot waveguide devices for low-cost biochemical sensor applications.
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Alasaarela T, Karvonen L, Jussila H, Säynätjoki A, Mehravar S, Norwood RA, Peyghambarian N, Kieu K, Tittonen I, Lipsanen H. High-quality crystallinity controlled ALD TiO2 for waveguiding applications. OPTICS LETTERS 2013; 38:3980-3983. [PMID: 24321899 DOI: 10.1364/ol.38.003980] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We demonstrate a novel atomic layer deposition (ALD) process to make high-quality nanocrystalline titanium dioxide (TiO(2)) with intermediate Al(2)O(3) layers to limit the crystal size. The process is based on titanium chloride (TiCl(4))+water and trimethyl aluminum (TMA)+ozone processes at 250°C deposition temperature. The waveguide losses measured using a prism coupling method for 633 and 1551 nm wavelengths are as low as 0.2±0.1 dB/mm with the smallest crystal size, with losses increasing with crystal size. In comparison, plain TiO(2) deposited at 250°C without the intermediate Al(2)O(3) layers shows high scattering losses and is not viable as waveguide material. The third-order optical nonlinearity decreases with smaller crystal size as verified by third-harmonic generation microscopy but still remains high for all samples. Crystallinity controlled ALD-grown TiO(2) is an excellent candidate for various optical applications, where good thermal stability and high third-order optical nonlinearity are needed.
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Stenberg P, Roussey M, Ryczkowski P, Genty G, Honkanen S, Kuittinen M. A merged photonic crystal slot waveguide embedded in ALD-TiO₂. OPTICS EXPRESS 2013; 21:24154-24162. [PMID: 24104325 DOI: 10.1364/oe.21.024154] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We demonstrate the concept of a merged nanoscale photonic crystal slot waveguide that acts as a bandpass filter in the near infrared region of the spectrum. The device is based on the integration of a photonic crystal cavity in a slot waveguide on a silicon on insulator substrate. The device is further embedded in amorphous titanium dioxide using atomic layer deposition, which allows to reduce two-photon absorption losses and creates the possibility to combine nonlinear guided-wave optics resulting from the strong field confinement in the slot region with slow light effects in the photonic crystal cavity. Our approach is fully compatible with complementary metal oxide semiconductor technology and opens up new perspectives for the integration of all-optical signal processing functionalities in hybrid silicon nanophotonics platforms.
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Erdmanis M, Karvonen L, Säynätjoki A, Tu X, Liow TY, Lo QG, Vänskä O, Honkanen S, Tittonen I. Towards broad-bandwidth polarization-independent nanostrip waveguide ring resonators. OPTICS EXPRESS 2013; 21:9974-9981. [PMID: 23609703 DOI: 10.1364/oe.21.009974] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We demonstrate a new method for accessing the broad-bandwidth polarization-independent operation of a microring resonator based on the standard photonic nanostrip waveguides. The method employs the selective application of atomic layer deposition to form highly uniform TiO(2) overlayers with the specific dispersion properties. The wide operation window is achieved by matching the wavelength dependencies of the free spectral ranges of the two orthogonal polarizations.
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Affiliation(s)
- M Erdmanis
- Aalto University, Department of Micro- and Nanosciences, Tietotie 3, FI-02150 Espoo, Finland.
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Choy JT, Bradley JDB, Deotare PB, Burgess IB, Evans CC, Mazur E, Lončar M. Integrated TiO2 resonators for visible photonics. OPTICS LETTERS 2012; 37:539-541. [PMID: 22344099 DOI: 10.1364/ol.37.000539] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We demonstrate waveguide-coupled titanium dioxide (TiO(2) racetrack resonators with loaded quality factors of 2.2×10(4) for the visible wavelengths. The structures were fabricated in sputtered TiO(2) thin films on oxidized silicon substrates using standard top-down nanofabrication techniques, and passively probed in transmission measurements using a tunable red laser.
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Affiliation(s)
- Jennifer T Choy
- School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.
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Saleem MR, Stenberg P, Alasaarela T, Silfsten P, Khan MB, Honkanen S, Turunen J. Towards athermal organic-inorganic guided mode resonance filters. OPTICS EXPRESS 2011; 19:24241-24251. [PMID: 22109450 DOI: 10.1364/oe.19.024241] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We demonstrate guided-mode resonance filters featuring an amorphous TiO(2) layer fabricated by atomic layer deposition on a polymeric substrate. The thermal properties of such filters are studied in detail by taking into account both thermal expansion of the structure and thermo-optic coefficients of the materials. We show both theoretically and experimentally that these two effects partially compensate for each other, leading to nearly athermal devices. The wavelength shift of the resonance reflectance peak (< 1 nm) is a small fraction of the peak width (~11 nm) up to temperatures exceeding the room temperature by tens of degrees centigrade.
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Affiliation(s)
- M R Saleem
- University of Eastern Finland, Department of Physics and Mathematics, P.O. Box 111, FI-80101 Joensuu, Finland.
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Alasaarela T, Zheng D, Huang L, Priimagi A, Bai B, Tervonen A, Honkanen S, Kuittinen M, Turunen J. Single-layer one-dimensional nonpolarizing guided-mode resonance filters under normal incidence. OPTICS LETTERS 2011; 36:2411-2413. [PMID: 21725428 DOI: 10.1364/ol.36.002411] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We demonstrate that properly designed one-dimensional guided-mode resonance filters (GMRFs) with only one grating layer can exhibit a nonpolarizing resonant filtering effect under normal incidence. A sinusoidal profile nonpolarizing GMRF is realized by photoinduced surface-relief grating formation on thin films of polymer-azobenzene complexes and subsequent atomic layer deposition, showing the feasibility of fabrication of such compact GMRFs.
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Affiliation(s)
- Tapani Alasaarela
- Deparment of Micro- and Nanosciences, Aalto University, P.O. Box 13500, FI-00076 Aalto, Finland
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Alasaarela T, Korn D, Alloatti L, Säynätjoki A, Tervonen A, Palmer R, Leuthold J, Freude W, Honkanen S. Reduced propagation loss in silicon strip and slot waveguides coated by atomic layer deposition. OPTICS EXPRESS 2011; 19:11529-11538. [PMID: 21716384 DOI: 10.1364/oe.19.011529] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
When silicon strip and slot waveguides are coated with a 50 nm amorphous titanium dioxide (TiO2) film, measured losses at a wavelength of 1.55 μm can be as low as (2 ± 1)dB/cm and (7 ± 2)dB/cm, respectively. We use atomic layer deposition (ALD), estimate the effect of ALD growth on the surface roughness, and discuss the effect on the scattering losses. Because the gap between the rails of a slot waveguide narrows by the TiO2 deposition, the effective slot width can be back-end controlled. This is useful for precise adjustment if the slot is to be filled with, e. g., a nonlinear organic material or with a sensitizer for sensors applications.
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Affiliation(s)
- T Alasaarela
- Department of Micro and Nanosciences, Aalto University School of Electrical Engineering, Aalto, Finland.
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Saastamoinen T, Alasaarela T, Lehmuskero A, Vartiainen I, Heikkilä N, Kuittinen M. Resonance waveguide reflectors with semi-wide bandwidth at the visible wavelengths. OPTICS EXPRESS 2011; 19:2126-2132. [PMID: 21369030 DOI: 10.1364/oe.19.002126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We present a resonance waveguide grating with relatively wide bandwidth in the visible region of the spectrum compared to typical resonance structures. The reflective properties of the grating are based on amorphous atomic layer deposited titanium dioxide which has rather high refractive index at the visible wavelengths. The resonance grating provides approximately 20-30 nm bandwidth with over 90% reflectance at the visible wavelengths. The measured reflectances of the fabricated elements show also very good agreement with the theoretical predictions. These kind of reflectors may be useful in applications that make use of LED sources.
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Affiliation(s)
- Toni Saastamoinen
- University of Eastern Finland, Department of Physics and Mathematics, P.O.Box 111, FI-80101 Joensuu, Finland.
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Vapaavuori J, Valtavirta V, Alasaarela T, Mamiya JI, Priimagi A, Shishido A, Kaivola M. Efficient surface structuring and photoalignment of supramolecular polymer–azobenzene complexes through rational chromophore design. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm12642c] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lehmuskero A, Vartiainen I, Saastamoinen T, Alasaarela T, Kuittinen M. Absorbing polarization selective resonant gratings. OPTICS EXPRESS 2010; 18:27270-27279. [PMID: 21197005 DOI: 10.1364/oe.18.027270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We introduce resonant absorbers that consist of linear metal wires embedded inside of a titanium dioxide grating. We show that in these structures the guided-mode resonance may lead to the almost total absorption of one polarization component and greatly enhance the absorption in localized surface plasma resonance. In addition, we show that the structures have potential to function as filters or polarizing beamsplitters. Absorption of 99.67 % has been obtained together with the contrast of 6600 at the wavelength of 532 nm. This corresponds the extinction of 8.8597. The results have been verified experimentally by fabricating an absorbing filter with electron beam lithography and atomic layer deposition technique. The absorption is remarkably high considering the thickness of the structures which is only 219-333 nm.
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Affiliation(s)
- Anni Lehmuskero
- University of Eastern Finland, Department of Physics and Mathematics, Joensuu, Finland.
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