Two-Dimensional Photogalvanic Spin-Battery

TL;DR

This paper introduces a novel 2D spin-battery device based on the photogalvanic effect in phosphorene that generates pure spin-currents without charge flow, promising for spintronics and energy harvesting.

Contribution

It proposes a new 2D spin-battery system utilizing the photogalvanic effect, demonstrating its stability and feasibility through numerical and first principles calculations.

Findings

Generates pure spin-current without charge-current at zero bias.

Device stability against structural and material variations.

First principles calculations support the PGE-based operation.

Abstract

Pure spin-current is of central importance in spintronics. Here we propose a two-dimensional (2D) spin-battery system that delivers pure spin-current without an accompanying charge-current to the outside world at zero bias. The principle of the spin-battery roots in the photogalvanic effect (PGE), and the system has good operational stability against structural perturbation, photon energy and other materials detail. The device principle is numerically implemented in the 2D material phosphorene as an example, and first principles calculations give excellent qualitative agreement with the PGE physics. The 2D spin-battery is interesting as it is both a device that generates pure spin-currents, also an energy source that harvests photons. Given the versatile operational space, the spin-battery should be experimentally feasible.