Aharonov-Bohm effect in charge-density wave loops with inherent temporal current switching

M. Tsubota¹, K. Inagaki^1,2, T. Matsuura¹ and S. Tanda^1,2

¹ Department of Applied Physics, Hokkaido University - Sapporo 060-8628, Japan
² Center of Education and Research for Topological Science and Technology, Hokkaido University Sapporo 060-8628, Japan

Received: 28 July 2011
Accepted: 7 February 2012

Abstract

We report evidence for Aharonov-Bohm (AB) oscillations with temporal current switching at 5.1 and 79 K by using charge-density wave (CDW) loops in TaS₃ ring crystals. The periodicity of the AB oscillations is h/2e, and this is confirmed by employing four samples with different diameters. This means that sliding CDWs carry 2e charge quanta. We observe current switching between the two states, namely the high and low current states, as a result of the separation of field-dependent and time-dependent fluctuations. The probability distribution of the switching oscillates also with a period of h/2e. We discover that the observed oscillations, which are a superposition of the current fluctuations and the switching behavior, have a period h/2e.