Spin torque transistor revisited

TL;DR

This paper enhances the spin-torque transistor's differential current gain by integrating magnetic insulators and the spin Hall effect, enabling negative differential resistance and large gain, thus advancing spintronics functionality.

Contribution

It introduces two innovations—magnetic insulators and the spin Hall effect—to improve the differential gain of spin-torque transistors, a key step forward for spintronics applications.

Findings

Achieved negative differential resistance in spin-torque transistors.

Demonstrated large differential gain over a broad parameter space.

Functionality maintained with a normal metal film using the spin Hall effect.

Abstract

This paper reports on the improvement of the differential current gain in the spin-torque transistor based on two independent innovations, viz.the use of magnetic insulators and the spin Hall effect. Since, except for a few examples, spin transistors lack the current gain that is essential for many applications, spintronics and magnetic information technology lack an essential functionality compared to CMOS devices. Here, we show that negative differential resistance and large differential gain is possible in a large region of parameter space of the spin torque transistor. We also demonstrate that functionality is preserved when the control part is replaced by a normal metal film with a large spin Hall angle.