Electric-field control of tunneling magnetoresistance effect in a Ni/InAs/Ni quantum-dot spin valve

TL;DR

This paper demonstrates electric-field control of tunneling magnetoresistance in a Ni/InAs/Ni quantum-dot spin valve, showing modulation and sign reversal of TMR via gate voltage near Coulomb blockade peaks.

Contribution

It introduces a method to electrically manipulate TMR in a quantum-dot spin valve, enabling control over magnetic effects in semiconductor devices.

Findings

TMR effect is significantly modulated near Coulomb blockade peaks.

The sign of TMR can be switched by adjusting gate voltage.

Coulomb blockade oscillations observed at small bias voltage.

Abstract

We demonstrate an electric-field control of tunneling magnetoresistance (TMR) effect in a semiconductor quantum-dot (QD) spin-valve device. By using ferromagnetic Ni nano-gap electrodes, we observe the Coulomb blockade oscillations at a small bias voltage. In the vicinity of the Coulomb blockade peak, the TMR effect is significantly modulated and even its sign is switched by changing the gate voltage, where the sign of the TMR value changes at the resonant condition.