Quantum tunneling time of a Bose-Einstein condensate traversing through a laser-induced potential barrier

TL;DR

This paper investigates how atomic nonlinearity influences the tunneling time of a Bose-Einstein condensate through a laser-induced barrier, revealing dramatic effects including violation of the Hartman effect and negative tunneling times.

Contribution

It introduces a method to control atomic nonlinearity locally during tunneling and demonstrates its significant impact on tunneling dynamics in BECs.

Findings

Atomic nonlinearity dramatically alters tunneling behavior.

Violation of the Hartman effect observed.

Negative tunneling times occur under certain conditions.

Abstract

We theoretically study the effect of atomic nonlinearity on the tunneling time in the case of an atomic Bose-Einstein condensate (BEC) traversing the laser-induced potential barrier. The atomic nonlinearity is controlled to appear only in the region of the barrier by employing the Feshbach resonance technique to tune interatomic interaction in the tunneling process. Numerical simulation shows that the atomic nonlinear effect dramatically changes the tunneling behavior of the BEC matter wave packet, and results in the violation of Hartman effect and the occurrence of negative tunneling time.