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Title: Invited Article: An integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument

Abstract

We report on the development of the first integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument, covering an ultra wide spectral range from 3 cm{sup −1} to 7000 cm{sup −1} (0.1–210 THz or 0.4–870 meV). The instrument comprises four sub-systems, where the magneto-cryostat-transfer sub-system enables the usage of the magneto-cryostat sub-system with the mid-infrared ellipsometer sub-system, and the far-infrared/terahertz ellipsometer sub-system. Both ellipsometer sub-systems can be used as variable angle-of-incidence spectroscopic ellipsometers in reflection or transmission mode, and are equipped with multiple light sources and detectors. The ellipsometer sub-systems are operated in polarizer-sample-rotating-analyzer configuration granting access to the upper left 3 × 3 block of the normalized 4 × 4 Mueller matrix. The closed cycle magneto-cryostat sub-system provides sample temperatures between room temperature and 1.4 K and magnetic fields up to 8 T, enabling the detection of transverse and longitudinal magnetic field-induced birefringence. We discuss theoretical background and practical realization of the integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument, as well as acquisition of optical Hall effect data and the corresponding model analysis procedures. Exemplarily, epitaxial graphene grown on 6H-SiC, a tellurium doped bulk GaAs sample and an AlGaN/GaN high electron mobility transistor structure are investigated. Themore » selected experimental datasets display the full spectral, magnetic field and temperature range of the instrument and demonstrate data analysis strategies. Effects from free charge carriers in two dimensional confinement and in a volume material, as well as quantum mechanical effects (inter-Landau-level transitions) are observed and discussed exemplarily.« less

Authors:
; ;  [1]; ;  [2]
  1. Department of Electrical Engineering and Center for Nanohybrid Functional Materials, University of Nebraska-Lincoln, Lincoln, Nebraska 68588 (United States)
  2. J. A. Woollam Co., Inc., 645 M Street, Suite 102, Lincoln, Nebraska 68508-2243 (United States)
Publication Date:
OSTI Identifier:
22308667
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 85; Journal Issue: 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BIREFRINGENCE; CHARGE CARRIERS; CRYOSTATS; DATA ANALYSIS; DETECTION; DOPED MATERIALS; ELECTRON MOBILITY; FAR INFRARED RADIATION; GALLIUM ARSENIDES; GALLIUM NITRIDES; GRAPHENE; HALL EFFECT; LIGHT SOURCES; MAGNETIC FIELDS; QUANTUM MECHANICS; REFLECTION; SILICON CARBIDES; TELLURIUM; TEMPERATURE RANGE 0273-0400 K; TRANSISTORS

Citation Formats

Kühne, P., E-mail: kuehne@huskers.unl.edu, Schubert, M., E-mail: schubert@engr.unl.edu, Hofmann, T., E-mail: thofmann@engr.unl.edu, Herzinger, C. M., E-mail: cherzinger@jawoollam.com, and Woollam, J. A., E-mail: jwoollam@jawoollam.com. Invited Article: An integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument. United States: N. p., 2014. Web. doi:10.1063/1.4889920.
Kühne, P., E-mail: kuehne@huskers.unl.edu, Schubert, M., E-mail: schubert@engr.unl.edu, Hofmann, T., E-mail: thofmann@engr.unl.edu, Herzinger, C. M., E-mail: cherzinger@jawoollam.com, & Woollam, J. A., E-mail: jwoollam@jawoollam.com. Invited Article: An integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument. United States. doi:10.1063/1.4889920.
Kühne, P., E-mail: kuehne@huskers.unl.edu, Schubert, M., E-mail: schubert@engr.unl.edu, Hofmann, T., E-mail: thofmann@engr.unl.edu, Herzinger, C. M., E-mail: cherzinger@jawoollam.com, and Woollam, J. A., E-mail: jwoollam@jawoollam.com. Tue . "Invited Article: An integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument". United States. doi:10.1063/1.4889920.
@article{osti_22308667,
title = {Invited Article: An integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument},
author = {Kühne, P., E-mail: kuehne@huskers.unl.edu and Schubert, M., E-mail: schubert@engr.unl.edu and Hofmann, T., E-mail: thofmann@engr.unl.edu and Herzinger, C. M., E-mail: cherzinger@jawoollam.com and Woollam, J. A., E-mail: jwoollam@jawoollam.com},
abstractNote = {We report on the development of the first integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument, covering an ultra wide spectral range from 3 cm{sup −1} to 7000 cm{sup −1} (0.1–210 THz or 0.4–870 meV). The instrument comprises four sub-systems, where the magneto-cryostat-transfer sub-system enables the usage of the magneto-cryostat sub-system with the mid-infrared ellipsometer sub-system, and the far-infrared/terahertz ellipsometer sub-system. Both ellipsometer sub-systems can be used as variable angle-of-incidence spectroscopic ellipsometers in reflection or transmission mode, and are equipped with multiple light sources and detectors. The ellipsometer sub-systems are operated in polarizer-sample-rotating-analyzer configuration granting access to the upper left 3 × 3 block of the normalized 4 × 4 Mueller matrix. The closed cycle magneto-cryostat sub-system provides sample temperatures between room temperature and 1.4 K and magnetic fields up to 8 T, enabling the detection of transverse and longitudinal magnetic field-induced birefringence. We discuss theoretical background and practical realization of the integrated mid-infrared, far-infrared, and terahertz optical Hall effect instrument, as well as acquisition of optical Hall effect data and the corresponding model analysis procedures. Exemplarily, epitaxial graphene grown on 6H-SiC, a tellurium doped bulk GaAs sample and an AlGaN/GaN high electron mobility transistor structure are investigated. The selected experimental datasets display the full spectral, magnetic field and temperature range of the instrument and demonstrate data analysis strategies. Effects from free charge carriers in two dimensional confinement and in a volume material, as well as quantum mechanical effects (inter-Landau-level transitions) are observed and discussed exemplarily.},
doi = {10.1063/1.4889920},
journal = {Review of Scientific Instruments},
number = 7,
volume = 85,
place = {United States},
year = {Tue Jul 15 00:00:00 EDT 2014},
month = {Tue Jul 15 00:00:00 EDT 2014}
}
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