Vacuum decay and fermion total reflection by the Klein step

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.

References in corpus (1)

• Exact Pair Production Rate for a Smooth Potential Step

Cited by in corpus (3)

• Evolution of strictly localized states in non-interacting quantum field theories with background fields
• Dynamically assisted Klein tunneling in the Furry picture
• Dynamically assisted pair production in subcritical potential step and particle--anti-particle interpretations