Aharonov-Bohm effect in the tunnelling of a quantum rotor in a linear Paul trap

TL;DR

This paper demonstrates the Aharonov-Bohm effect in a quantum tunnelling system using trapped ions, revealing magnetic flux dependence of tunnelling rates and advancing understanding of quantum tunnelling dynamics.

Contribution

It introduces a novel quantum tunnelling system with ionic structures in a linear Paul trap that exhibits the Aharonov-Bohm effect during tunnelling, a previously unobserved phenomenon.

Findings

Tunnelling rate depends periodically on magnetic field strength.

The period of tunnelling rate oscillation matches the magnetic flux quantum.

The system confirms the coupling of charged particles to the vector potential during tunnelling.

Abstract

Quantum tunnelling is a common fundamental quantum-mechanical phenomenon that originates from the wave-like characteristics of quantum particles. Although the quantum-tunnelling effect was first observed 85 years ago, some questions regarding the dynamics of quantum tunnelling remain unresolved. Here, we realise a quantum-tunnelling system using two-dimensional ionic structures in a linear Paul trap. We demonstrate that the charged particles in this quantum-tunnelling system are coupled to the vector potential of a magnetic field throughout the entire process, even during quantum tunnelling, as indicated by the manifestation of the Aharonov-Bohm effect in this system. The tunnelling rate of the structures periodically depends on the strength of the magnetic field, whose period is the same as the magnetic-flux quantum $\phi_0$ through the rotor [($0.99 \pm 0.07)\times \phi_0$].