Persistent currents in a Peierls insulator

Abstract

Mesoscopic rings with an incommensurate charge density wave (CDW) ground state are investigated theoretically. It is found that the magnetic flux has a pronounced effect on the amplitude of the CDW order parameter. Self-consistent calculations predict a periodic modulation of the order parameter as a function of the flux. In sufficiently small rings the magnetic field can even destroy the CDW ground state. The flux-induced phase transition affects the persistent current and should be observable in the magnetic response.

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

“…Another theory states that quasi-particle interference is generated by changing the CDW ground state [15,16,17]. Latyshev et al tried to observe the AB effect of CDWs in NbSe 3 crystals with tiny random holes pierced by heavy-ion irradiation [18].…”

Mesoscopic charge density wave in a magnetic flux

“…When N is even, the effect of an AB flux is to destabilize the CDW, as found in refs. 2 . But when N is odd, we find that the CDW can be stabilized by the flux, contrary to the conclusions of refs.…”

Comment on “Peierls Gap in a Mesoscopic Ring Threaded by a Magnetic Flux”

“…The main result is that a threading flux tends to suppress the Peierls instability, as also claimed in another recent work [2]. This interesting result is only partly correct because it does not properly take into account the parity effect essential in a 1D ring: the thermodynamics depends crucially on the parity of the number N e of electrons (forgetting the spin) [3,4].…”