Electronically Driven Magnetoelectric Coupling in Co/La:Hf0.5Zr0.5O2 Heterostructures for Energy-Efficient Neuromorphic Computing

TL;DR

This paper shows how electric fields can efficiently control magnetism in a material system compatible with modern electronics, enabling energy-efficient computing.

Contribution

The novel contribution is demonstrating electrically driven magnetoelectric coupling in a CMOS-compatible Co/La:Hf0.5Zr0.5O2 system with low energy consumption and multilevel response.

Findings

Electric field induces a 5% modulation of saturation magnetization in cobalt via ferroelectric switching.

Energy consumption is as low as 6 nJ with minimal leakage current (10 nA/cm² at 500 mV).

Multilevel magnetoelectric response suggests potential for neuromorphic computing applications.

Abstract

Magnetoelectric materials
enable low-power memory devices by leveraging
the electric control of magnetization. The discovery of ferroelectricity
in doped hafnia has unlocked further opportunities since the distinct
ferroelectric switching mechanism in this material can enable robust
and multilevel modulation of magnetization by electric field, if combined
with appropriate magnetic materials. Here, we demonstrate a 5% electric
field-induced modulation of the saturation magnetization in a cobalt
layer, driven by ferroelectric switching of an adjacent epitaxial
La­(1%):Hf0.5Zr0.5O2 film. Dichroic
imaging with synchrotron radiation confirms that ferroelectric switching
induces a magnetic change. We show that the response time is faster
than 500 ns (limited by the setup time resolution threshold) and that
energy consumption is 6 nJ. This low energy consumption is mainly
enabled by the absence of relevant leakage current contribution (10
nA/cm2 at 500 mV). The found response time and energy-efficient
behavior point to the presence of an electronically driven modulation
of magnetism (i.e., conventional magnetoelectric effects), which is
confirmed by theoretical calculations and compositional analysis.
Additionally, a multilevel magnetoelectric response is observed, enabling
neuromorphic-like behavior. The demonstration of magnetoelectric coupling
in a system based on CMOS-compatible materials offers a viable route
toward the development of low-power beyond von-Neumann technologies.

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