Access to Klein Tunneling via Space-Time Modulation
Quantum Physics
2026-04-17 v3 High Energy Physics - Theory
Abstract
We show that space-time modulation of electromagnetic potentials enables Klein tunneling far below the static threshold. The derived kinematics reveal oblique transitions that can connect opposite-energy continua without requiring their overlap, yielding a velocity-tunable Klein gap where transmission vanishes within a finite velocity window and reemerges beyond. The associated reduction in energy thresholds -- by up to four orders of magnitude -- suggests the potential for experimental realization using flying-focus fronts and relativistic electron beams.
Cite
@article{arxiv.2510.21154,
title = {Access to Klein Tunneling via Space-Time Modulation},
author = {Furkan Ok and Amir Bahrami and Christophe Caloz},
journal= {arXiv preprint arXiv:2510.21154},
year = {2026}
}