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arXiv · 1012.2937

Phonon Transport in Suspended Single Layer Graphene

Xiangfan Xu·Yu Wang·Kaiwen Zhang·Xiangming Zhao·Sukang Bae·Martin Heinrich·Cong Tinh Bui·Rongguo Xie·John T. L. Thong·Byung Hee Hong·Kian Ping Loh·Baowen Li·Barbaros Oezyilmaz
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Abstract

We report the first temperature dependent phonon transport measurements in suspended Cu-CVD single layer graphene (SLG) from 15K to 380K using microfabricated suspended devices. The thermal conductance per unit cross section $\sigma$/A increases with temperature and exhibits a peak near T~280K ($\pm$10K) due to the Umklapp process. At low temperatures (T<140K), the temperature dependent thermal conductivity scales as ~T^{1.5}, suggesting that the main contribution to thermal conductance arises from flexural acoustic (ZA) phonons in suspended SLG. The $\sigma$/A reaches a high value of 1.7$\times10^5 T^{1.5}$ W/m^2K, which is approaching the expected ballistic phonon thermal conductance for two-dimensional graphene sheets. Our results not only clarify the ambiguity in the thermal conductance, but also demonstrate the potential of Cu-CVD graphene for heat related applications.

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Xiangfan Xu, Yu Wang, Kaiwen Zhang, Xiangming Zhao, Sukang Bae, Martin Heinrich, Cong Tinh Bui, Rongguo Xie, John T. L. Thong, Byung Hee Hong, Kian Ping Loh, Baowen Li, Barbaros Oezyilmaz. 2010-12-14. Phonon Transport in Suspended Single Layer Graphene. https://arxiv.org/abs/1012.2937

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