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arXiv · 1306.0375

Energy and particle number fluctuations in superconducting heterostructures

Ville J. Kauppila·Matti A. Laakso·Tero T. Heikkilä
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Abstract

We consider fluctuations of the energy on a mesoscopic island coupled to two leads. We use the Keldysh effective action formalism to derive the Langevin equation for the energy of the island in a very general setting and show how the Langevin equation for the case of uncorrelated tunneling events is derived from a more general one. As an application of the theory, we consider a superconducting island coupled to two normal metal leads and calculate the statistics of the temperature (in the quasiequilibrium case) and the number of quasiparticle excitations on the island.

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Ville J. Kauppila, Matti A. Laakso, Tero T. Heikkilä. 2013-06-03. Energy and particle number fluctuations in superconducting heterostructures. https://arxiv.org/abs/1306.0375

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