Macroscopic Klein Tunneling in spin-orbit coupled Bose-Einstein Condensates

TL;DR

This paper proposes an experimental setup using spin-orbit coupled Bose-Einstein condensates to observe macroscopic Klein tunneling, demonstrating that such relativistic quantum phenomena can be detected in a controllable, nonlinear quantum system.

Contribution

It introduces a method to realize a nonlinear Dirac equation with tunable parameters in BECs and demonstrates the feasibility of observing macroscopic Klein tunneling experimentally.

Findings

Macroscopic Klein tunneling can be detected in spin-orbit coupled BECs.

A negative energy BEC can transmit through a Gaussian potential barrier.

Numerical simulations confirm the feasibility under realistic conditions.

Abstract

We propose an experimental scheme to detect macroscopic Klein tunneling with spin-orbit coupled Bose-Einstein condensates (BECs). We show that a nonlinear Dirac equation with tunable parameters can be realized with such BECs. %in a simple configuration to generate the artificial spin-orbit coupling. Through numerical calculations, we demonstrate that macroscopic Klein tunneling can be clearly detected under realistic conditions. Macroscopic quantum coherence in such relativistic tunneling is clarified and a BEC with a negative energy is shown to be able to transmit transparently through a wide Gaussian potential barrier.