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arXiv · 2003.04637

Nanotechnological Structure for Observation of Current Induced Contact Potential Difference and Creation of Effective Cooper Pair Mass-Spectroscopy

Todor M. Mishonov·Albert M. Varonov
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Abstract

Changes of the electron work-function of a superconductor proportional to the square of the current density $Δϕ= -βj^2$ are known as Bernoulli effect in superconductors or current induced Contact Potential Difference (CPD). The temperature dependent constant $β(T;m^{\star})$ is parametrized by the effective mass of Cooper pairs $m^{\star}$. In such a way the study of the Bernoulli effect leads to creation of Cooper pair mass-spectroscopy. In this paper a short review on the Bernoulli effect in superconductors is given and a proposed experimental set-up for its measurement is described in detail. The experiment requires standard electronic equipment and can be implemented in every laboratory related to physics of superconductivity. This experimental set-up for observation of current induced CPD requires nano-technological hybrid superconductor structures with atomically clean interfaces and measurement of nano-volt signals with capacitive coupling to the sample.

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Todor M. Mishonov, Albert M. Varonov. 2020-03-10. Nanotechnological Structure for Observation of Current Induced Contact Potential Difference and Creation of Effective Cooper Pair Mass-Spectroscopy. https://doi.org/10.1016/j.physc.2020.1353712

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