# Reversal of thermoelectric current in tubular nanowires

## TL;DR

This paper predicts that in tubular nanowires, a transverse magnetic field can reverse the thermoelectric current direction, a phenomenon that persists despite impurities, with implications for various nanowire types.

## Contribution

It demonstrates the magnetic field-induced reversal of thermoelectric current in tubular nanowires, including core/shell, surface state, and topological insulator nanowires.

## Key findings

- Current reverses sign with increasing temperature bias under strong magnetic fields.
- Landau and snaking states cause non-monotonic energy dispersion leading to current reversal.
- Reversal effect persists even with impurities.

## Abstract

We calculate the charge current generated by a temperature bias between the two ends of a tubular nanowire. We show that in the presence of a transversal magnetic field the current can change sign, i.e., electrons can either flow from the hot to the cold reservoir, or in the opposite direction, when the temperature bias increases. This behavior occurs when the magnetic field is sufficiently strong, such that Landau and snaking states are created, and the energy dispersion is non-monotonic with respect to the longitudinal wave vector. The sign reversal can survive in the presence of impurities. We predict this result for core/shell nanowires, for uniform nanowires with surface states due to the Fermi level pinning, and for topological insulator nanowires.