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arXiv · 1605.05877

Energy fluctuations of finite free-electron Fermi gas

Jukka P. Pekola·Paolo Muratore-Ginanneschi·Antti Kupiainen·Yuri M. Galperin
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Abstract

We discuss the energy distribution of free-electron Fermi-gas, a problem with a textbook solution of Gaussian energy fluctuations in the limit of a large system. We find that for a small system, characterized solely by its heat capacity $C$, the distribution can be solved analytically, and it is both skewed and it vanishes at low energies, exhibiting a sharp drop to zero at the energy corresponding to the filled Fermi sea. The results are relevant from the experimental point of view, since the predicted non-Gaussian effects become pronounced when $C/k_B \lesssim 10^3$ ($k_B$ is the Boltzmann constant), a regime that can be easily achieved for instance in mesoscopic metallic conductors at sub-kelvin temperatures.

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Jukka P. Pekola, Paolo Muratore-Ginanneschi, Antti Kupiainen, Yuri M. Galperin. 2016-05-19. Energy fluctuations of finite free-electron Fermi gas. https://doi.org/10.1103/physreve.94.022123

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