Miniature Magnetic Nano islands in a Morphotropic Cobaltite Matrix

TL;DR

This paper reports the creation of switchable magnetic nano-islands within a cobaltite matrix, enabling high-density magnetic storage with precise control over magnetic states at the nanoscale.

Contribution

It introduces a novel method to construct and control magnetic nano-islands in a nonmagnetic matrix using epitaxial strain and atomically sharp boundaries.

Findings

Magnetic nano-islands as small as 35 nm were achieved.

A high areal density of 400 Gbit/in² was demonstrated.

Regionally controlled magnetic states enable potential for scalable memory devices.

Abstract

High-density magnetic memories are key components in spintronics, quantum computing, and energy-efficient electronics. Reduced dimensionality and magnetic domain stability at the nanoscale are essential for the miniaturization of magnetic storage units. Yet, inducing magnetic order, and selectively tuning spin-orbital coupling at specific locations have remained challenging. Here we demonstrate the construction of switchable magnetic nano-islands in a nonmagnetic matrix based on cobaltite homo-structures. The magnetic and electronic states are laterally modified by epitaxial strain, which is regionally controlled by freestanding membranes. Atomically sharp grain boundaries isolate the crosstalk between magnetically distinct regions. The minimal size of magnetic nano-islands reaches 35 nm in diameter, enabling an areal density of 400 Gbit per inch square. Besides providing an ideal platform for precisely controlled read and write schemes, this methodology can enable scalable and patterned memories on silicon and flexible substrates for various applications.