Temperature-dependent elastic constants of thorium dioxide probed using time-domain Brillouin scattering
| العنوان: | Temperature-dependent elastic constants of thorium dioxide probed using time-domain Brillouin scattering |
|---|---|
| المؤلفون: | Amey Khanolkar, Yuzhou Wang, Cody A. Dennett, Zilong Hua, J. Matthew Mann, Marat Khafizov, David H. Hurley |
| المصدر: | Journal of Applied Physics. 133 |
| بيانات النشر: | AIP Publishing, 2023. |
| سنة النشر: | 2023 |
| مصطلحات موضوعية: | Condensed Matter - Materials Science, N/A, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Physics and Astronomy, Applied Physics (physics.app-ph), Physics - Applied Physics |
| الوصف: | We report the adiabatic elastic constants of single-crystal thorium dioxide over a temperature range of 77 - 350 K. Time-domain Brillouin scattering (TDBS), an all-optical, non-contact picosecond ultrasonic technique, is used to generate and detect coherent acoustic phonons that propagate in the bulk perpendicular to the surface of the crystal. These coherent acoustic lattice vibrations have been monitored in two hydrothermally grown single-crystal thorium dioxide samples along the (100) and (311) crystallographic directions. The three independent elastic constants of the cubic crystal (C11, C12 and C44) are determined from the measured bulk acoustic velocities. The longitudinal wave along the (100) orientation provided a direct measurement of C11. Measurement of C44 and C12 was achieved by enhancing the intensity of quasi-shear mode in a (311) oriented crystal by adjusting the polarization angle relative to the crystal axes. We find the magnitude of softening of the three elastic constants to be ~2.5% over the measured temperature range. Good agreement is found between the measured elastic constants with previously reported values at room temperature, and between the measured temperature-dependent bulk modulus with calculated values. We find that semi-empirical models capturing lattice anharmonicity adequately reproduce the observed trend. We also determine the acoustic Gruneisen anharmonicity parameter from the experimentally derived temperature-dependent bulk modulus and previously reported temperature-dependent values of volume thermal expansion coefficient and heat capacity. This work presents measurements of the temperature-dependent elasticity in single-crystal thorium dioxide at cryogenic temperature and provides a basis for testing ab initio theoretical models and evaluating the impact of anharmonicity on thermophysical properties. Manuscript submitted to a peer-reviewed journal |
| تدمد: | 1089-7550 0021-8979 |
| DOI: | 10.1063/5.0148866 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ec8950f6035832802ed9da405e4f7ba5 https://doi.org/10.1063/5.0148866 |
| Rights: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....ec8950f6035832802ed9da405e4f7ba5 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10897550 00218979 |
|---|---|
| DOI: | 10.1063/5.0148866 |