Elastic-instability-driven nonvolatile multiferroic-like coupling

Magnetoelectric (ME) transduction in conventional multiferroics relies on weak intrinsic coupling between magnetic and electric orders, often restricted by low operating temperatures due to symmetry constraints. Here, we present a materials-agnostic strategy for bistable ME coupling through elastic snap-through instability in a mechanically engineered composite. The system consists of a trilayer arch structure, with two magnetically responsive elastomer layers sandwiching a charged electret film. Under an applied magnetic field, magnetoelastic forces drive a snap-through transition, switching the electret polarization between two stable, mechanically distinct states. This bistability enables nonvolatile ME switching without relying on intrinsic ferroic order parameters. Experiments demonstrate reproducible transitions, robust state retention, and a tunable ME response governed by geometric parameters. Furthermore, the introduction of additional mechanical degrees of freedom enhances design flexibility, enabling control over the symmetry of the ME response by adjusting the electret layer position. Based on these results, we demonstrate a nonvolatile ME memory element that supports magnetic-field writing and electrical-state reading via AC interrogation. These findings establish elastic instability as a versatile mechanism for bistable magnetoelectricity, offering a scalable and energy-efficient platform for future memory and logic devices.