Correlated Persistent Tunneling Currents in Glasses

TL;DR

This paper models how magnetic fields influence low-temperature tunneling currents in glasses, explaining recent permittivity observations and predicting oscillations due to quantum interference effects.

Contribution

It introduces a generalized tunneling model incorporating magnetic flux effects on charged particles in glasses, explaining experimental permittivity sensitivity and predicting oscillatory behavior.

Findings

Magnetic fields cause flux periodic energy level shifts in tunneling systems.

Dipole-dipole and elastic interactions enhance magnetic effects at low temperatures.

Oscillations in permittivity as a function of magnetic field are predicted.

Abstract

Low temperature properties of glasses are derived within a generalized tunneling model, considering the motion of charged particles on a closed path in a double-well potential. The presence of a magnetic induction field B violates the time reversal invariance due to the Aharonov-Bohm phase, and leads to flux periodic energy levels. At low temperature, this effect is shown to be strongly enhanced by dipole-dipole and elastic interactions between tunneling systems and becomes measurable. Thus, the recently observed strong sensitivity of the electric permittivity to weak magnetic fields can be explained. In addition, superimposed oscillations as a function of the magnetic field are predicted.