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arXiv · 2008.08578

Loop spin effects in intense background fields

Anton Ilderton·Ben King·Suo Tang
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Abstract

Radiative and non-radiative electron spin flip probabilities are analysed in both plane wave and focussed laser backgrounds. We provide a simple and physically transparent description of spin dynamics in plane waves, and demonstrate that there exists a kinematic regime in which the usual leading order perturbative hierarchy of QED is reversed, and non-radiative loop effects dominate over radiative tree-level spin-flips. We show that while this loop-dominance becomes suppressed in focussed laser pulses due to a high sensitivity to field geometry, there is nevertheless a regime in which, in principle, loop effects on spin transitions can be discerned.

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Anton Ilderton, Ben King, Suo Tang. 2020-08-19. Loop spin effects in intense background fields. https://doi.org/10.1103/physrevd.102.076013

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