On the upper limit of thermal conductivity GaN crystals
نویسنده
چکیده
The maximal value of thermal conductivity κmax of the perfect wurzite GaN crystal containing isotopes of natural abundance is estimated. Our upper limit of κ = 4800 W/Km at Tmax = 32 K is smaller than calculated by Liu and Balandin κ = 6000 W/Km and higher than obtained by Slack et al κ = 3750W/Km. The phenomenological dependence κ ∝ T obtained by Mion et al for the temperature interval 300− 450K is extended to 200 − 300 K. For temperatures higher than Tmax 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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