Force-Based Reading and Writing of Individual Single-Atom Magnets

TL;DR

This paper demonstrates a method to read and write the spin states of individual holmium atoms on a surface using magnetic exchange force microscopy, advancing atomic-scale data storage technology with low energy loss.

Contribution

It introduces a novel mechanical approach to control and detect single-atom spins, enabling high-density, low-heat magnetic data storage at the atomic scale.

Findings

Successful readout of holmium atom spin orientation via exchange forces

Controlled writing of spin states by mechanical tip approach

Potential for atomic-scale, low-energy data storage

Abstract

The integration of single-atom bits enables the realization of the highest data-density memory. Reading and writing information to these bits through mechanical interactions opens the possibility of operating the magnetic devices with low heat generation and high density recording. To achieve this visionary goal, we demonstrate the use of magnetic exchange force microscopy to read and write the spin orientation of individual holmium adatoms on MgO thin films. The spin orientation of the holmium adatom is stabilized by the strong uniaxial anisotropy of the adsorption site and can be read out by measuring the exchange forces between the magnetic tip and the atom. The spin orientation can be written by approaching the tip closer to the holmium adatom.We explain this writing mechanism by the symmetry reduction of the adsorption site of the Ho adatom. These findings demonstrate the potential for information storage with minimal energy loss and pave the way for a new field of atomic-scale mechano-spintronics.