Aharonov-Bohm oscillations caused by non-topological surface states in Dirac nanowires

摘要

One intriguing fingerprint of surface states in topological insulators is theAharonov-Bohm effect in magnetoconductivity of nanowires. We show that surfacestates in nanowires of Dirac materials (bismuth, bismuth antimony, and lead tinchalcogenides) being in non-topological phase, exhibit the same effect asamendment to magnetoconductivity of the bulk states. We consider a simple modelof a cylindrical nanowire, which is described by the 3D Dirac equation with ageneral $T$-invariant boundary condition. The boundary condition is determinedby a single phenomenological parameter whose sign defines topological-like andnon-topological surface states. The non-topological surface states emergeoutside the gap. In longitudinal magnetic field $B$ they lead to Aharonov-Bohmamendment for the density of states and correspondingly for conductivity of thenanowire. The phase of these magnetooscillations increases with $B$ from $\pi$to $2\pi$.