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arXiv · 1911.10481

Lindblad approximation and spin relaxation in quantum electrodynamics

Laurent Amour·Jean Nourrigat
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Abstract

This article is concerned with the time evolution of a $\frac{1}{2}$-spin particle in a constant external magnetic field with the quantized electromagnetic field (photons). We derive a Lindblad (or GKLS) type approximation of the spin dynamics together with a precise control of the error coming from this approximation. The error term is bounded by $g^2$ where $g$ is the coupling constant of the spin-photon interaction. The point here is the uniformity in time $t>0$ of this error control.

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Laurent Amour, Jean Nourrigat. 2019-11-24. Lindblad approximation and spin relaxation in quantum electrodynamics. https://doi.org/10.1088/1751-8121%2Fab8e04

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