Semi-classical understanding of flux quantization in superconductors

Kolahal Bhattacharya

doi:10.1007/s40509-024-00343-6

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arXiv · 2308.14757

Semi-classical understanding of flux quantization in superconductors

Kolahal Bhattacharya

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Abstract

Like electric charge, magnetic flux is also quantised. Theoretically, one can show that the flux quantum must be h/e, as observed in the quantum Hall effect. However, in the superconducting systems, the flux quantum is experimentally observed as h/2e. There is no fundamental explanation for the empirical result. In this article, we argue that this phenomenon is fundamentally linked to the nonlocality problem of the Aharonov-Bohm effect and present a new semi-classical explanation for the magnetic flux quantum in superconductivity. This work will also show why the flux quantum should be h/e in the case of the quantum Hall effect.

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Kolahal Bhattacharya. 2023-08-19. Semi-classical understanding of flux quantization in superconductors. https://doi.org/10.1007/s40509-024-00343-6

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