| Autor: |
Adachi, K., Ogi, H., Nagakubo, A., Nakamura, N., Hirao, M., Imade, M., Yoshimura, M., Mori, Y. |
| Předmět: |
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| Zdroj: |
Journal of Applied Physics; 2016, Vol. 119 Issue 24, p245111-1-245111-6, 6p, 1 Diagram, 1 Chart, 3 Graphs |
| Abstrakt: |
Using the antenna-transmission resonant ultrasound spectroscopy, we measured the elastic constants of GaN between 10 and 305 K using 72 resonance frequencies. The mode Grüneisen parameter is determined from temperature dependence of each elastic constant, which is larger along the c axis than along the a axis, showing anisotropy in lattice anharmonicity. The zero-temperature elastic constants, determined using the Einstein-oscillator model, yield the Debye characteristic temperature of 636 K. The ab-initio calculation is carried out for deducing the elastic constants, and comparison between calculations and measurements at 0 K reveals that the local-density-approximation potential is preferable for theoretically evaluating characteristics of GaN. The theoretical calculation also supports the anisotropy in lattice anharmonicity. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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