Synchrotron radiation-based far-infrared spectroscopic ellipsometer with full Mueller-matrix capability

Journal Article · Fri Feb 15 00:00:00 EST 2013 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.4789495· OSTI ID:22105411

Stanislavchuk, T. N.; Kang, T. D.; Rogers, P. D.; Standard, E. C.; Basistyy, R.; Nita, G.; Zhou, T.; Sirenko, A. A. ^[1]; Kotelyanskii, A. M. ^[1]; Carr, G. L. ^[2]; Kotelyanskii, M. ^[1]

---

1. Department of Physics, New Jersey Institute of Technology, Newark, New Jersey 07102 (United States)
2. National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York 11973 (United States)

We developed far-IR spectroscopic ellipsometer at the U4IR beamline of the National Synchrotron Light Source in Brookhaven National Laboratory. This ellipsometer is able to measure both, rotating analyzer and full-Mueller matrix spectra using rotating retarders, and wire-grid linear polarizers. We utilize exceptional brightness of synchrotron radiation in the broad spectral range between about 20 and 4000 cm{sup -1}. Fourier-transform infrared (FT-IR) spectrometer is used for multi-wavelength data acquisition. The sample stage has temperature variation between 4.2 and 450 K, wide range of {theta}-2{theta} angular rotation, {chi} tilt angle adjustment, and X-Y-Z translation. A LabVIEW-based software controls the motors, sample temperature, and FT-IR spectrometer and also allows to run fully automated experiments with pre-programmed measurement schedules. Data analysis is based on Berreman's 4 Multiplication-Sign 4 propagation matrix formalism to calculate the Mueller matrix parameters of anisotropic samples with magnetic permeability {mu}{ne} 1. A nonlinear regression of the rotating analyzer ellipsometry and/or Mueller matrix (MM) spectra, which are usually acquired at variable angles of incidence and sample crystallographic orientations, allows extraction of dielectric constant and magnetic permeability tensors for bulk and thin-film samples. Applications of this ellipsometer setup for multiferroic and ferrimagnetic materials with {mu}{ne} 1 are illustrated with experimental results and simulations for TbMnO{sub 3} and Dy{sub 3}Fe{sub 5}O{sub 12} single crystals. We demonstrate how magnetic and electric dipoles, such as magnons and phonons, can be distinguished from a single MM measurement without adducing any modeling arguments. The parameters of magnetoelectric components of electromagnon excitations are determined using MM spectra of TbMnO{sub 3}.

• OSTI ID: 22105411
• Journal Information: Review of Scientific Instruments, Vol. 84, Issue 2; Other Information: (c) 2013 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION SPECTROSCOPY
BNL
DYSPROSIUM COMPOUNDS
ELECTRIC DIPOLES
ELLIPSOMETERS
ELLIPSOMETRY
FERRIMAGNETIC MATERIALS
FOURIER TRANSFORMATION
INFRARED SPECTRA
MAGNETIC SUSCEPTIBILITY
MATRICES
NSLS
SPECTROMETERS
SYNCHROTRON RADIATION
TERBIUM COMPOUNDS
THIN FILMS