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arXiv · 2411.14523

A relativistic QFT description for the interaction of a spin with a magnetic field

Ruhi Shah·Eduardo Martín-Martínez·T. Rick Perche
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Abstract

We analyze how non-relativistic effective models for the magnetic coupling of a spin to the electromagnetic field (proportional to $\hat{\boldsymbol{\sigma}}\cdot \boldsymbol{B}$) emerge from a full quantum field theoretical description of charged fermionic fields with the quantum electromagnetic field. This allows us to keep track of relativistic corrections to the models commonly used in experimental spin physics. We discuss how this interaction compares to the usual simplified models used in relativistic quantum information.

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Ruhi Shah, Eduardo Martín-Martínez, T. Rick Perche. 2024-11-21. A relativistic QFT description for the interaction of a spin with a magnetic field. https://doi.org/10.1103/physrevd.111.044075

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