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arXiv · 2009.14038

Electron-phonon coupling of epigraphene at millikelvin temperatures

Bayan Karimi·Hans He·Yu-Cheng Chang·Libin Wang·Jukka P. Pekola·Rositsa Yakimova·Naveen Shetty·Joonas T. Peltonen·Samuel Lara-Avila·Sergey Kubatkin
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Abstract

We investigate the basic charge and heat transport properties of charge neutral epigraphene at sub-kelvin temperatures, demonstrating nearly logarithmic dependence of electrical conductivity over more than two decades in temperature. Using graphene's sheet conductance as in-situ thermometer, we present a measurement of electron-phonon heat transport at mK temperatures and show that it obeys the $T^4$ dependence characteristic for clean two-dimensional conductor. Based on our measurement we predict the noise-equivalent power of $\sim 10^{-22}~{\rm W}/\sqrt{{\rm Hz}}$ of epigraphene bolometer at the low end of achievable temperatures.

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Bayan Karimi, Hans He, Yu-Cheng Chang, Libin Wang, Jukka P. Pekola, Rositsa Yakimova, Naveen Shetty, Joonas T. Peltonen, Samuel Lara-Avila, Sergey Kubatkin. 2020-09-29. Electron-phonon coupling of epigraphene at millikelvin temperatures. https://arxiv.org/abs/2009.14038

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