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Title: Temperature dependence of phonons in FeGe 2

Journal Article · · Physical Review Materials
 [1];  [1];  [1];  [1];  [2];  [3];  [4];  [4];  [1]
  1. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  2. St. Francis Xavier Univ., Antigonish, NS (Canada)
  3. Univ. of California, Riverside, CA (United States)
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Inelastic neutron scattering was used to measure phonon dispersions in a single crystal of FeGe2 with the C16 structure at 300, 500, and 635 K. Phonon densities of states (DOS) were also measured on polycrystalline FeGe2 from 325 to 1050 K, and the Fe partial DOS was obtained from polycrystalline 57FeGe2 at 300 K using nuclear resonant inelastic x-ray scattering. The dominant feature in the temperature dependence of the phonon spectrum is thermal broadening of high-energy modes. The energy shifts of the low- and high-energy parts of the spectrum were almost the same. DFT calculations performed with the quasiharmonic approximation gave results in moderate agreement with the experimental thermal energy shifts, although the isobaric Grüneisen parameter calculated from the quasiharmonic model was smaller than that from measurements. The thermal broadening of the phonon spectrum and dispersions, especially at high energies, indicates a cubic anharmonicity to second order that should also induce phonon shifts. Lastly, we show that different anharmonic contributions cancel out, giving average phonon shifts in moderate agreement to calculations with the quasiharmonic approximation. The different parts of the large phonon contribution to the entropy are separated for FeGe2, showing modest but interpretable anharmonic contributions.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
AC05-00OR22725; FG02-99ER45775; AC02-06CH11357; AC02-05CH11231; FG02-03ER46055; NA0001974
OSTI ID:
1528731
Alternate ID(s):
OSTI ID: 1477531
Journal Information:
Physical Review Materials, Vol. 2, Issue 10; ISSN 2475-9953
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 10 works
Citation information provided by
Web of Science

References (37)

Generalized Gradient Approximation Made Simple journal October 1996
Temperature-dependent effective third-order interatomic force constants from first principles journal October 2013
Magnetic structures in the iron-germanium system journal June 1965
Mantid—Data analysis and visualization package for neutron scattering and μ SR experiments
  • Arnold, O.; Bilheux, J. C.; Borreguero, J. M.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 764 https://doi.org/10.1016/j.nima.2014.07.029
journal November 2014
DAVE: A Comprehensive Software Suite for the Reduction, Visualization, and Analysis of Low Energy Neutron Spectroscopic Data
  • Azuah, Richard Tumanjong; Kneller, Larry R.; Qiu, Yiming
  • Journal of Research of the National Institute of Standards and Technology, Vol. 114, Issue 6 https://doi.org/10.6028/jres.114.025
journal November 2009
Magnetic structure and critical properties of FeGe 2 journal April 1985
Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set journal July 1996
Spintronics: A Spin-Based Electronics Vision for the Future journal November 2001
Phonon anharmonicity in silicon from 100 to 1500 K journal January 2015
Nuclear quantum effect with pure anharmonicity and the anomalous thermal expansion of silicon journal February 2018
Temperature dependent effective potential method for accurate free energy calculations of solids journal March 2013
Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set journal October 1996
First principles phonon calculations in materials science journal November 2015
From ultrasoft pseudopotentials to the projector augmented-wave method journal January 1999
High-energy magnetic excitations and anomalous spin-wave damping in FeGe 2 journal September 2000
Temperature dependence of phonons in Pd 3 Fe through the Curie temperature journal July 2018
Room temperature section of the phase diagram of the Cu-Fe-Ge ternary system journal August 1991
CONUSS and PHOENIX: Evaluation of nuclear resonant scattering data journal March 2000
Magnetic Properties of Intermetallic Compounds in Iron-Germanium System : Fe 1.67 Ge and FeGe 2 journal March 1961
Theory of the magnetic phase diagram and magnetostriction of FeGe 2 journal July 1989
Phonon anharmonicity and components of the entropy in palladium and platinum journal June 2016
Compounds and pseudo-binary alloys with the CuAl2(C16)-type structure I. Preparation and X-ray results journal May 1972
Scattering of Neutrons by an Anharmonic Crystal journal December 1962
Ab initiomolecular dynamics for liquid metals journal January 1993
Effects of composition, temperature, and magnetism on phonons in bcc Fe-V alloys journal October 2010
Itinerant magnetism and electronic properties of FeGe 2 journal September 1991
Magnetic phase transitions in FeGe2 journal June 1988
Antiferromagnetic structure of FeGe2 journal August 1964
Magnetostriction of antiferromagnetic FeGe2 journal November 1984
Calculation of dielectric susceptibility for complex ionic systems: Application to a predicted superlattice journal August 1989
Entropically Favored Ordering: The Metallurgy of Al 2 Cu Revisited journal June 2001
Reducing Dzyaloshinskii-Moriya interaction and field-free spin-orbit torque switching in synthetic antiferromagnets journal May 2021
High-resolution X-ray luminescence extension imaging journal February 2021
Entropically Favored Ordering: The Metallurgy of Al2Cu Revisited text January 2001
Temperature dependent effective potential method for accurate free energy calculations of solids text January 2013
First principles phonon calculations in materials science preprint January 2015
A nuclear quantum effect with pure anharmonicity and the anomalous thermal expansion of silicon text January 2016

Figures / Tables (12)


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