Spin current and rectification in Luttinger liquids

TL;DR

This paper shows that in a strongly interacting one-dimensional quantum wire, an ac voltage can generate a significant spin current without magnetic or spin-polarized injection, with potential for efficient spintronics.

Contribution

It introduces a mechanism for spin current generation in Luttinger liquids driven by ac voltage and magnetic field, without spin injection or dynamic magnetic fields.

Findings

Spin current can be generated by ac voltage in Luttinger liquids.

The spin current can surpass charge current in magnitude.

Spin current exhibits power-law dependence on voltage bias.

Abstract

We demonstrate that spin current can be generated by an ac voltage in a one-channel quantum wire with strong repulsive electron interactions in the presence of a non-magnetic impurity and uniform static magnetic field. In a certain range of voltages, the spin current can exhibit a power dependence on the ac voltage bias with a negative exponent. The spin current expressed in units of $\hbar/2$ per second can become much larger than the charge current in units of the electron charge per second. The spin current generation requires neither spin-polarized particle injection nor time-dependent magnetic fields.