Experimental Realization of a Quantum Spin Pump

TL;DR

This paper reports the experimental realization of a quantum spin pump that can generate pure spin currents without charge flow using cyclic RF excitation in a GaAs quantum dot, leveraging spin-dependent mesoscopic fluctuations.

Contribution

It demonstrates a novel quantum spin pump capable of producing pure spin currents, advancing spintronics and quantum information processing technologies.

Findings

Successfully pumped pure spin without charge

Utilized in-plane Zeeman field to induce spin dependence

Measured spin currents via spin-selective collector

Abstract

We demonstrate the operation of a quantum spin pump based on cyclic radio-frequency excitation of a GaAs quantum dot, including the ability to pump pure spin without pumping charge. The device takes advantage of bidirectional mesoscopic fluctuations of pumped current, made spin-dependent by the application of an in-plane Zeeman field. Spin currents are measured by placing the pump in a focusing geometry with a spin-selective collector.