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arXiv · 2111.06509

Vacuum decay and fermion total reflection by the Klein step

H. Nakazato·M. Ochiai
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Abstract

The so-called Klein tunneling is re-examined within the framework of quantum field theory, but from a different point of view on the asymptotic states. We treat it as a one-dimensional scattering process of a fermion incident to a step potential and introduce asymptotic operators as appropriate $t = \pm \infty$ limits of the field operator responsible for the process. For the so-called Klein energy range, two asymptotic vacua naturally emerge which are defined as states annihilated by the asymptotic annihilation operators. They are related by a similarity transformation, which entails a vacuum decay and yields a vacuum decay constant. When a fermion with incident energy in the Klein region is injected to the step, it is shown to be reflected with probability one, accompanied by fermion--anti-fermion pairs that are vacuum decay products.

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H. Nakazato, M. Ochiai. 2021-11-12. Vacuum decay and fermion total reflection by the Klein step. https://doi.org/10.1093/ptep/ptac085

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