Atomic-scale control of substrate-spin coupling via vertical manipulation of a 2D metal-organic framework

TL;DR

This study demonstrates atomic-scale control of substrate-spin interactions in a 2D kagome MOF by vertical manipulation, enabling reversible tuning of Kondo coupling with potential applications in spintronics.

Contribution

It introduces a method to reversibly control Kondo coupling in a 2D MOF through vertical manipulation using an STM probe, a novel approach for atomic-scale spin control.

Findings

Reversible control of Kondo coupling by adjusting adsorption height.

Mechanical manipulation alters exchange interactions at the atomic level.

Potential for designing spintronic devices with atomic precision.

Abstract

Two-dimensional (2D) materials with frustrated crystal geometries can host strongly correlated electrons, potentially leading to a range of exotic many-body quantum phases such as Mott insulators, quantum spin-liquids, and Kondo lattices. The ability to control exchange-coupling within these systems is therefore highly desirable. Here, we use an atomically sharp scanning tunneling microscope probe to vertically manipulate a 2D Mott insulating kagome metal-organic framework (MOF) featuring Kondo-screened local magnetic moments on Ag(111). We show that by controlling the adsorption height of the MOF, we can also controllably and reversibly change the strength of Kondo coupling between the MOF's local spins and the substrate's conduction electrons. This mechanical control of Kondo coupling could be extended to other forms of interlayer exchange coupling, potentially allowing for atomic-scale design or control of spintronics technologies.