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Wang J, Li Z, Zhao K, Dong S, Wu D, Meng W, Zhang J, Hou Y, Lu Y, Lu Q. Isolated scan unit and scanning tunneling microscope for stable imaging in ultra-high magnetic fields. Ultramicroscopy 2024; 261:113960. [PMID: 38547811 DOI: 10.1016/j.ultramic.2024.113960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 02/19/2024] [Accepted: 03/20/2024] [Indexed: 04/22/2024]
Abstract
The high resolution of a scanning tunneling microscope (STM) relies on the stability of its scan unit. In this study, we present an isolated scan unit featuring non-magnetic design and ultra-high stability, as well as bidirectional movement capability. Different types of piezoelectric motors can be incorporated into the scan unit to create a highly stable STM. The standalone structure of scan unit ensures a stable atomic imaging process by decreasing noise generated by motor. The non-magnetic design makes the scan unit work stable in high magnetic field conditions. Moreover, we have successfully constructed a novel STM based on the isolated scan unit, in which two inertial piezoelectric motors act as the coarse approach actuators. The exceptional performance of homebuilt STM is proved by the high-resolution atomic images and dI/dV spectrums on NbSe2 surface at varying temperatures, as well as the raw-data images of graphite obtained at ultra-high magnetic fields of 23 T. According to the literature research, no STM has previously reported the atomic image at extreme conditions of 2 K low temperature and 23 T ultra-high magnetic field. Additionally, we present the ultra-low drift rates between the tip and sample at varying temperatures, as well as when raising the magnetic fields from 0 T to 23 T, indicating the ultra-high stability of the STM in high magnetic field conditions. The outstanding performance of our stable STM hold great potential for investigating the materials in ultra-high magnetic fields.
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Affiliation(s)
- Jihao Wang
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China
| | - Zihao Li
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China; Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, Anhui, China
| | - Kesen Zhao
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China
| | - Shuai Dong
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China
| | - Dan Wu
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China
| | - Wenjie Meng
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China
| | - Jing Zhang
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China
| | - Yubin Hou
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China.
| | - Yalin Lu
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, Anhui, China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei Anhui 230026, China
| | - Qingyou Lu
- Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, Anhui, China; The High Magnetic Field Laboratory of Anhui Province, Hefei 230031, Anhui, China; Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, Anhui, China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei Anhui 230026, China; Hefei Science Center, Chinese Academy of Sciences, Hefei 230031, China.
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Zhao K, Zhang J, Meng W, Zheng S, Wang J, Feng Q, Wang Z, Hou Y, Lu Q, Lu Y. Cryogenic spectroscopic imaging scanning tunnelling microscope in a water-cooled magnet down to 1.7 K. Ultramicroscopy 2023; 253:113773. [PMID: 37315346 DOI: 10.1016/j.ultramic.2023.113773] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 04/19/2023] [Accepted: 05/30/2023] [Indexed: 06/16/2023]
Abstract
Spectroscopic-imaging scanning tunnelling microscope (SI-STM) in a water-cooled magnet (WM) at low temperature has long been desirable in the condensed matter physics area since it is crucial for addressing various scientific problems, such as the behaviour of Cooper electrons crossing Hc2 in a high-temperature superconductor. Here we report on the construction and performance of the first atomically resolved cryogenic SI-STM in a WM. It operates at low temperatures of down to 1.7 K and in magnetic fields of up to 22 T (the WM's upper safety limit). The WM-SI-STM unit features a high-stiffness sapphire-based frame with the lowest eigenfrequency being 16 kHz. A slender piezoelectric scan tube (PST) is coaxially embedded in and glued to the frame. A well-polished zirconia shaft is spring-clamped onto the gold-coated inner wall of the PST to serve both the stepper and the scanner. The microscope unit as a whole is elastically suspended in a tubular sample space inside a 1K-cryostat by a two-stage internal passive vibrational reduction system, achieving a base temperature below 2 K in a static exchange gas. We demonstrate the SI-STM by imaging TaS2 at 50 K and FeSe at 1.7 K. Detecting the well-defined superconducting gap of FeSe, an iron-based superconductor, at variable magnetic fields demonstrates the device's spectroscopic imaging capability. The maximum noise intensity at the typical frequency is 3 pA per square root Hz at 22 T, which is only slightly worse than at 0 T, indicating the insensitivity of the STM to harsh conditions. In addition, our work shows the potential of SI-STMs for use in a WM and hybrid magnet with a 50 mm-bore size where high fields can be generated.
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Affiliation(s)
- Kesen Zhao
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei Institudes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China
| | - Jing Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei Institudes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China
| | - Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei Institudes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China.
| | - Shaofeng Zheng
- University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China
| | - Jihao Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei Institudes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China
| | - Qiyuan Feng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei Institudes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China
| | - Ze Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei Institudes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China
| | - Yubin Hou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei Institudes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China.
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei Institudes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China; University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, People's Republic of China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China; Hefei Science Center Chinese Academy of Sciences, Hefei 230031, People's Republic of China.
| | - Yalin Lu
- University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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3
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Wang J, Li W, Meng W, Hou Y, Lu Y, Lu Q. Atomic imaging with a 12 T magnetic field perpendicular or parallel to the sample surface by an ultra-stable scanning tunneling microscope. Ultramicroscopy 2023; 251:113774. [PMID: 37270856 DOI: 10.1016/j.ultramic.2023.113774] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 05/30/2023] [Indexed: 06/06/2023]
Abstract
We present the first nonmetallic scanning tunneling microscope (STM) featuring an ultra-stable tip-sample mechanical loop and capable of atomic-resolution imaging within a 12 T magnetic field that could be either perpendicular or parallel to the sample surface. This is also the first STM with an ultra-stable tip-sample mechanical loop but without a standalone scanner. The STM head is constructed only with two parts: an improved spider-drive motor and a zirconia tip holder. The motor performs both the coarse approach and atomic imaging. A supporting spring is set at the fixed end of the motor tube to decrease the tip-sample mechanical loop. The zirconia tip holder performs as the frame of the whole STM head. With the novel design, the STM head in three dimensions can be as small as 7.9 mm × 7.9 mm × 26.5 mm. The device's excellent performance is demonstrated by atomic-resolution images of graphite and NbSe2 obtained at 300 K and 2 K, as well as the high-resolution dI/dV spectrums of NbSe2 at variable temperatures. Low drift rates in the X-Y plane and Z direction further prove the imaging stability of our new STM. High-quality imaging of the Charge Density Wave (CDW) structure on a TaS2 surface shows the STM's good application capability. Continuous atomic images obtained in magnetic fields rangs from 0 T to 12 T with the direction of the magnetic field perpendicular or parallel to the sample surface show the STM's good immunity to high magnetic fields. Our results illustrate the new STM's broad application ability in extreme conditions of low temperature and high magnetic field.
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Affiliation(s)
- Jihao Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, China
| | - Weixuan Li
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, China
| | - Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, China
| | - Yubin Hou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, China.
| | - Yalin Lu
- Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, China; Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026 China
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, Anhui 230031, China; The High Magnetic Field Laboratory of Anhui Province, Hefei, Anhui 230031, China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, China; Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026 China; Hefei Science Center, Chinese Academy of Sciences, Hefei 230031, China.
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Atomically resolved low-temperature scanning tunneling microscope operating in a 22 T water-cooled magnet. Ultramicroscopy 2023; 245:113668. [PMID: 36565650 DOI: 10.1016/j.ultramic.2022.113668] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 11/08/2022] [Accepted: 12/17/2022] [Indexed: 12/23/2022]
Abstract
We present the design and construction of a nonmetallic tip-sample mechanical loop featured Scanning Tunneling Microscope (STM) that operates in a 22 T water-cooled magnet at a low temperature of l.8 K. The STM head mainly consists of a spider-drive motor, stand-alone scanner, moveable sapphire sample holder, and sapphire frame. All parts exist in the tip-sample mechanical loop are made of sapphire to reduce the interference from high magnetic fields. Except for the necessary movement of the tip and scanner, all STM parts are stationary. More importantly, the tip-sample mechanical loop is separate from the motor after detecting the tunneling current, which helps prevent the high voltage signal interference from entering the tip-sample junction, leading to a high stable imaging. A Janis liquid helium cryostat is used to obtain a variable temperature range from 1.8 K to 300 K, and the STM head is cooled down via helium exchange gas. The STM head hangs at the bottom of a probe with a two-stage spring suspension to prevent the huge vibration generated by the water-cooled magnet from entering the tip-sample junction. The performance is demonstrated by atomically resolved STM images of graphite surface at 0 T and 22.8 T under room temperature. Furthermore, the obtained atomic-resolution images of NbSe2 at 1.8 K and 22 T, as well as high-resolution dI/dV spectrums at temperatures from 1.8 K to 8.5 K and magnetic fields from 0 T to 22 T are displayed. This is the first STM capable of atomic-resolution imaging and dI/dV measurement at 1.8 K in a 22 T water-cooled magnet. The high immunity to the magnetic field makes the nonmetallic tip-sample mechanical loop widely useable for atomic-resolution STM imaging in ultra-high magnetic field conditions.
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Li W, Wang J, Zhang J, Meng W, Xie C, Hou Y, Xia Z, Lu Q. Atomic-Resolution Imaging of Micron-Sized Samples Realized by High Magnetic Field Scanning Tunneling Microscopy. MICROMACHINES 2023; 14:287. [PMID: 36837986 PMCID: PMC9961884 DOI: 10.3390/mi14020287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/03/2023] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Scanning tunneling microscopy (STM) can image material surfaces with atomic resolution, making it a useful tool in the areas of physics and materials. Many materials are synthesized at micron size, especially few-layer materials. Limited by their complex structure, very few STMs are capable of directly positioning and imaging a micron-sized sample with atomic resolution. Traditional STMs are designed to study the material behavior induced by temperature variation, while the physical properties induced by magnetic fields are rarely studied. In this paper, we present the design and construction of an atomic-resolution STM that can operate in a 9 T high magnetic field. More importantly, the homebuilt STM is capable of imaging micron-sized samples. The performance of the STM is demonstrated by high-quality atomic images obtained on a graphite surface, with low drift rates in the X-Y plane and Z direction. The atomic-resolution image obtained on a 32-μm graphite flake illustrates the new STM's ability of positioning and imaging micron-sized samples. Finally, we present atomic resolution images at a magnetic field range from 0 T to 9 T. The above advantages make our STM a promising tool for investigating the quantum hall effect of micron-sized layered materials.
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Affiliation(s)
- Weixuan Li
- College of Metrology and Measurement Engineering, China Jiliang University (CJLU), Hangzhou 310018, China
| | - Jihao Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei 230031, China
| | - Jing Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei 230031, China
| | - Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei 230031, China
| | - Caihong Xie
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei 230031, China
| | - Yubin Hou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei 230031, China
| | - Zhigang Xia
- College of Metrology and Measurement Engineering, China Jiliang University (CJLU), Hangzhou 310018, China
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
- High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei 230031, China
- Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei 230026, China
- Hefei Science Center, Chinese Academy of Sciences, Hefei 230031, China
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Fernández-Lomana M, Wu B, Martín-Vega F, Sánchez-Barquilla R, Álvarez-Montoya R, Castilla JM, Navarrete J, Marijuan JR, Herrera E, Suderow H, Guillamón I. Millikelvin scanning tunneling microscope at 20/22 T with a graphite enabled stick-slip approach and an energy resolution below 8 μeV: Application to conductance quantization at 20 T in single atom point contacts of Al and Au and to the charge density wave of 2H-NbSe 2. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:093701. [PMID: 34598511 DOI: 10.1063/5.0059394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 08/21/2021] [Indexed: 06/13/2023]
Abstract
We describe a scanning tunneling microscope (STM) that operates at magnetic fields up to 22 T and temperatures down to 80 mK. We discuss the design of the STM head, with an improved coarse approach, the vibration isolation system, and efforts to improve the energy resolution using compact filters for multiple lines. We measure the superconducting gap and Josephson effect in aluminum and show that we can resolve features in the density of states as small as 8 μeV. We measure the quantization of conductance in atomic size contacts and make atomic resolution and density of states images in the layered material 2H-NbSe2. The latter experiments are performed by continuously operating the STM at magnetic fields of 20 T in periods of several days without interruption.
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Affiliation(s)
- Marta Fernández-Lomana
- Laboratorio de Bajas Temperaturas y Altos Campos Magnéticos, Unidad Asociada (UAM/CSIC), Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Beilun Wu
- Laboratorio de Bajas Temperaturas y Altos Campos Magnéticos, Unidad Asociada (UAM/CSIC), Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Francisco Martín-Vega
- Laboratorio de Bajas Temperaturas y Altos Campos Magnéticos, Unidad Asociada (UAM/CSIC), Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Raquel Sánchez-Barquilla
- Laboratorio de Bajas Temperaturas y Altos Campos Magnéticos, Unidad Asociada (UAM/CSIC), Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Rafael Álvarez-Montoya
- Laboratorio de Bajas Temperaturas y Altos Campos Magnéticos, Unidad Asociada (UAM/CSIC), Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - José María Castilla
- Departamento de Física de la Materia Condensada, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - José Navarrete
- SEGAINVEX, Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | | | - Edwin Herrera
- Laboratorio de Bajas Temperaturas y Altos Campos Magnéticos, Unidad Asociada (UAM/CSIC), Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Hermann Suderow
- Laboratorio de Bajas Temperaturas y Altos Campos Magnéticos, Unidad Asociada (UAM/CSIC), Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Isabel Guillamón
- Laboratorio de Bajas Temperaturas y Altos Campos Magnéticos, Unidad Asociada (UAM/CSIC), Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
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7
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A new view on the origin of zero-bias anomalies of Co atoms atop noble metal surfaces. Nat Commun 2020; 11:6112. [PMID: 33257648 PMCID: PMC7705691 DOI: 10.1038/s41467-020-19746-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 10/21/2020] [Indexed: 11/08/2022] Open
Abstract
Many-body phenomena are paramount in physics. In condensed matter, their hallmark is considerable on a wide range of material characteristics spanning electronic, magnetic, thermodynamic and transport properties. They potentially imprint non-trivial signatures in spectroscopic measurements, such as those assigned to Kondo, excitonic and polaronic features, whose emergence depends on the involved degrees of freedom. Here, we address systematically zero-bias anomalies detected by scanning tunneling spectroscopy on Co atoms deposited on Cu, Ag and Au(111) substrates, which remarkably are almost identical to those obtained from first-principles. These features originate from gaped spin-excitations induced by a finite magnetic anisotropy energy, in contrast to the usual widespread interpretation relating them to Kondo resonances. Resting on relativistic time-dependent density functional and many-body perturbation theories, we furthermore unveil a new many-body feature, the spinaron, resulting from the interaction of electrons and spin-excitations localizing electronic states in a well defined energy.
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Wang J, Geng T, Meng W, Huang P, Zhao K, Zhang J, Feng Q, Guo T, Xiang K, Hou Y, Chen W, Lu Y, Lu Q. A hybrid magnet based scanning tunneling microscope. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:053702. [PMID: 32486730 DOI: 10.1063/1.5140423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 04/24/2020] [Indexed: 06/11/2023]
Abstract
In this paper, a scanning tunneling microscope (STM) is presented that operates in a 27.5 T magnetic field within a hybrid magnet. The coarse approach of the STM is realized by using an inertial piezoelectric motor, and the scanning is realized by using a miniature scanner, which stands alone on a sapphire base. A combined vibration isolation system consisting of a brick-rubber-brick stack and two springs is used to isolate the vibration generated from the magnet. An enclosed copper shield is used to prevent sound from entering the tip-sample junction. The sound and vibration isolation measures highly improve the stability of the STM imaging. All the materials selected to construct the STM head are nonmagnetic. The drift rates of the STM in the X-Y plane and Z direction are as low as 26.2 pm/min and 34.6 pm/min, respectively, under ambient conditions. The high performance of the homebuilt STM was demonstrated by graphite hexagonal lattice images obtained in magnet fields ranging from 0 T to 27.5 T even without the protection of a vacuum and low temperatures. As far as known, this is the first STM that operates in a hybrid magnet. It is also the first STM that can obtain graphite hexagonal lattice images in magnetic fields up to 27.5 T. Our results greatly contribute to the further STM studies under ambient conditions and ultrahigh magnetic fields.
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Affiliation(s)
- Jihao Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Tao Geng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Pengcheng Huang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Kesen Zhao
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Jing Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Qiyuan Feng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Tengfei Guo
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Kui Xiang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yubin Hou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Wenge Chen
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yalin Lu
- Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
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9
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Meng W, Zhao K, Wang J, Zhang J, Feng Q, Wang Z, Geng T, Guo T, Hou Y, Pi L, Lu Y, Lu Q. 30 T scanning tunnelling microscope in a hybrid magnet with essentially non-metallic design. Ultramicroscopy 2020; 212:112975. [PMID: 32278228 DOI: 10.1016/j.ultramic.2020.112975] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/17/2020] [Accepted: 03/11/2020] [Indexed: 11/26/2022]
Abstract
We report on the construction and performance of the first hybrid resistive-superconducting magnet (HM) based scanning tunnelling microscope (STM) above 30 T. This custom-design HM-STM features a novel design of the STM head unit, whose tip-sample approach is implemented using a slender piezoelectric tube (PZT). The scanner shares part of PZT by fixing a sapphire frame onto the front quarter of PZT to construct a compact tip-sample loop, realising an outer diameter of 8.8 mm, which makes it compatible with a narrow sample space. Its main components are made of non-metallic materials of sapphire, which allows it to be immune from eddy currents and to operate under the condition of strong magnetic field fluctuation from a hybrid magnet, as well as cryogen-free cryocooler magnet systems. To analyse the stiffness of the STM head unit, the eigenfrequencies with 11 kHz and 12 kHz in bending modes, 25 kHz in a torsional mode, and 67 kHz in a longitudinal mode were simulated by finite element analysis; also, the drifting rates of the STM in ambient conditions in the X-Y plane and Z direction were measured at 25.5 and 38.2 pm/min, respectively. We present the first atomic images in magnetic fields up to 30.1 T in an HM. The raw data show the stable and distinguished performance while ramping up to maximum fields, indicating the new device's potential capability of operating in the future 45T-hybrid magnet and hundred-field pulsed magnet. Meanwhile, our compact and concentric cylindrical STM insert can operate in the low-temperature tubular sample space housed by the HM bore to develop low-temperature and extreme high-magnetic field STM.
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Affiliation(s)
- Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Kesen Zhao
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Jihao Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Jing Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Qiyuan Feng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Ze Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Tao Geng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Tengfei Guo
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yubin Hou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China.
| | - Li Pi
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China; Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Yalin Lu
- Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, China; Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China; Hefei Science Center, Chinese Academy of Sciences, Hefei 230031, China
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory and High Magnetic Field Laboratory of Anhui Province, Chinese Academy of Sciences, Hefei, Anhui 230031, China; Anhui Laboratory of Advanced Photon Science and Technology, University of Science and Technology of China, Hefei, Anhui 230026, China; Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China; Hefei Science Center, Chinese Academy of Sciences, Hefei 230031, China.
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10
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Wang J, Hou Y, Geng T, Zhang J, Feng Q, Xiang K, Chen F, Luo X, Sun Y, Meng W, Lu Y, Lu Q. A variable-temperature scanning tunneling microscope operated in a continuous flow cryostat. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2019; 90:093702. [PMID: 31575269 DOI: 10.1063/1.5118676] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 08/06/2019] [Indexed: 06/10/2023]
Abstract
We present a continuous flow cryostat scanning tunneling microscope (STM) which can be operated at temperatures between 4.9 K and 300 K. A variable temperature insert with 20 mm aperture is installed in the cryostat. A base temperature of 4.9 K at the STM head was achieved with helium exchange gas cooling. By using a novel design of zirconia structure, the size of the STM head was minimized to 9.2 mm in outer diameter. The high compactness and rigidity of the STM head make it less sensitive to vibrations, contributing to the high stability of the tip-sample junction. The drifting rates of the STM at 4.9 K in the X-Y plane and Z direction are 1.96 and 3.05 pm/min, respectively. The performance of the STM was demonstrated by atomically resolved imaging of graphite and NbSe2 without using external vibrational isolation. Furthermore, the dI/dV spectra of NbSe2 were resolved near its critical temperature, illustrating the formation process of the superconducting gap as a function of temperature. This STM is ultrahigh vacuum and strong magnetic field compatible, making it promising for direct application in the extreme conditions involving water-cooled magnets and hybrid magnets.
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Affiliation(s)
- Jihao Wang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Yubin Hou
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Tao Geng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Jing Zhang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Qiyuan Feng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Kui Xiang
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Fangchu Chen
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China
| | - Xuan Luo
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China
| | - Yunping Sun
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Wenjie Meng
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
| | - Yalin Lu
- Hefei Science Center Chinese Academy of Sciences, Hefei 230031, China
| | - Qingyou Lu
- Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory of the Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China
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11
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Rossi L, Gerritsen JW, Nelemans L, Khajetoorians AA, Bryant B. An ultra-compact low temperature scanning probe microscope for magnetic fields above 30 T. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:113706. [PMID: 30501346 DOI: 10.1063/1.5046578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/18/2018] [Indexed: 06/09/2023]
Abstract
We present the design of a highly compact high field scanning probe microscope (HF-SPM) for operation at cryogenic temperatures in an extremely high magnetic field, provided by a water-cooled Bitter magnet able to reach 38 T. The HF-SPM is 14 mm in diameter: an Attocube nano-positioner controls the coarse approach of a piezoresistive atomic force microscopy cantilever to a scanned sample. The Bitter magnet constitutes an extreme environment for scanning probe microscopy (SPM) due to the high level of vibrational noise; the Bitter magnet noise at frequencies up to 300 kHz is characterized, and noise mitigation methods are described. The performance of the HF-SPM is demonstrated by topographic imaging and noise measurements at up to 30 T. Additionally, the use of the SPM as a three-dimensional dilatometer for magnetostriction measurements is demonstrated via measurements on a magnetically frustrated spinel sample.
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Affiliation(s)
- L Rossi
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
| | - J W Gerritsen
- Institute of Molecules and Materials, Radboud University, Nijmegen, The Netherlands
| | - L Nelemans
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
| | - A A Khajetoorians
- Institute of Molecules and Materials, Radboud University, Nijmegen, The Netherlands
| | - B Bryant
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
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12
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Pabbi L, Binion AR, Banerjee R, Dusch B, Shoop CB, Hudson EW. ANITA-An active vibration cancellation system for scanning probe microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:063703. [PMID: 29960563 DOI: 10.1063/1.5033457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The high sensitivity of scanning probe microscopes poses a barrier to their use in noisy environments. Vibrational noise, whether from structural or acoustic sources, can manifest as relative motion between the probe tip and sample, which then appears in the probe position ("Z") feedback as it tries to cancel this motion. Here we describe an active cancellation process that nullifies the appearance of this vibration by adding a drive signal into the existing Z-feedback loop. The drive is digitally calculated from accelerometer-based vibration measurements. By transferring the vibration cancellation effort to this drive signal, vibration-created noise is significantly reduced. This inexpensive and easy solution requires no major instrumental modifications and is ideal for those looking to place their microscopes in noisier environments, coupled, for example, to active refrigeration systems (e.g., pulse tube cryocoolers) or other high-vibration instruments.
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Affiliation(s)
- L Pabbi
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - A R Binion
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - R Banerjee
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - B Dusch
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - C B Shoop
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - E W Hudson
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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