Large voltage tuning of Dzyaloshinskii-Moriya Interaction: a route towards dynamic control of skyrmion chirality

TL;DR

This paper demonstrates a significant electric field-induced variation in Dzyaloshinskii-Moriya Interaction (DMI) in ultrathin films, enabling dynamic control of skyrmion properties for spintronic applications.

Contribution

It reports the first large voltage tuning of DMI in ultrathin films, showing potential for electric control of skyrmion chirality and device engineering.

Findings

130% variation of DMI with electric field

Monotonic change of skyrmion size with electric field

Potential for DMI sign reversal and chirality switching

Abstract

Electric control of magnetism is a prerequisite for efficient and low power spintronic devices. More specifically, in heavy metal/ ferromagnet/ insulator heterostructures, voltage gating has been shown to locally and dynamically tune magnetic properties like interface anisotropy and saturation magnetization. However, its effect on interfacial Dzyaloshinskii-Moriya Interaction (DMI), which is crucial for the stability of magnetic skyrmions, has been challenging to achieve and has not been reported yet for ultrathin films. Here, we demonstrate 130% variation of DMI with electric field in Ta/FeCoB/TaOx trilayers through Brillouin Light Spectroscopy (BLS). Using polar- Magneto-Optical-Kerr-Effect microscopy, we further show a monotonic variation of DMI and skyrmionic bubble size with electric field, with an unprecedented efficiency. We anticipate through our observations that a sign reversal of DMI with electric field is possible, leading to a chirality switch. This dynamic manipulation of DMI establishes an additional degree of control to engineer programmable skyrmion based memory or logic devices.