Enhancement and suppression of tunneling by controlling symmetries of a potential barrier

TL;DR

This paper reveals that in certain 2D quantum systems, symmetry-controlled barriers can cause particles to prefer tunneling over classical traversal, a phenomenon absent in 1D systems.

Contribution

It introduces a novel class of 2D systems where symmetry of the potential barrier influences tunneling behavior, challenging classical intuition.

Findings

Particles prefer tunneling through symmetric barriers in 2D.

Symmetry induces effective potential barriers without real barriers.

The effect is unique to 2D systems, not present in 1D.

Abstract

We present a class of 2D systems which shows a counterintuitive property that contradicts a semi classical intuition: A 2D quantum particle "prefers" tunneling through a barrier rather than traveling above it. Viewing the one particle 2D system as the system of two 1D particles, it is demonstrated that this effect occurs due to a specific symmetry of the barrier that forces excitations of the interparticle degree of freedom that, in turn, leads to the appearance of an effective potential barrier even though there is no "real" barrier. This phenomenon cannot exist in 1D.