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arXiv · 0705.4187

On the upper limit of thermal conductivity GaN crystals

B. A. Danilchenko·I. A. Obukhov·T. Paszkiewicz·S. Wolski·A. Jezowski
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Abstract

The maximal value of thermal conductivity κ_{max} of the perfect wurzite GaN crystal containing isotopes of natural abundance is estimated. Our upper limit of κ=4800 W/Km at T_{max}=32 K is smaller than calculated by Liu and Balandin κ=6000 W/Km and higher than obtained by Slack et al κ=3750 W/Km. The phenomenological dependence κ\propto T^{-1.43} obtained by Mion et al for the temperature interval 300-450 K is extended to 200-300K. For temperatures higher than T_max the best fitting of our experimental data to Callaway's formula is obtained for Grueneisen's constant equal to γ= 1.35.

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B. A. Danilchenko, I. A. Obukhov, T. Paszkiewicz, S. Wolski, A. Jezowski. 2007-06-22. On the upper limit of thermal conductivity GaN crystals. https://doi.org/10.1016/j.ssc.2007.08.007

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