Modulation of ferromagnetism in (In,Fe)As quantum wells via electrically controlled deformation of the electron wavefunctions

TL;DR

This paper demonstrates electrical control of ferromagnetism in (In,Fe)As quantum wells by modulating electron wavefunctions with gate voltage, achieving significant Curie temperature changes with minimal carrier concentration variation.

Contribution

It introduces a novel method to control ferromagnetism via wavefunction overlap modulation in quantum wells, enabling low power and ultrafast magnetic manipulation.

Findings

Curie temperature changed by 42% with gate voltage.

Carrier concentration change was 2-3 orders of magnitude smaller.

Wavefunction overlap controls ferromagnetic properties effectively.

Abstract

We demonstrate electrical control of ferromagnetism in field-effect transistors with a trilayer quantum well (QW) channel containing an ultrathin n-type ferromagnetic semiconductor (In,Fe)As layer. A gate voltage is applied to control the electron wavefunctions {\phi}i in the QW, such that the overlap of {\phi}i and the (In,Fe)As layer is modified. The Curie temperature is largely changed by 42%, whereas the change in sheet carrier concentration is 2 - 3 orders of magnitude smaller than that of previous gating experiments. This result provides a new approach for versatile, low power, and ultrafast manipulation of magnetization.