Diamond-based sensing of stray fields from the bulk of thin-film magnets via nano-indentation

TL;DR

This paper introduces a non-destructive, nanoscale method combining nano-indentation and diamond magnetometers to measure the intrinsic magnetization of thin-film magnets by detecting their stray fields at specific locations.

Contribution

It presents a novel approach to directly measure bulk stray fields in thin films using nano-indentation and diamond magnetometers, enabling nanoscale spatial resolution.

Findings

Successfully measured stray fields in iron thin films

Determined intrinsic magnetization in the bulk of thin films

Provided a new method for studying magnetic properties of nanomaterials

Abstract

Measurement of the magnetization in the bulk of thin-film or two-dimensional materials is important for understanding their intrinsic properties without the complications from edges or domain walls. However, the stray fields from the bulk vanish or are very weak, which limits the application of direct measurement methods. Here, we develop a non-destructive approach to directly measuring the stray fields from the bulk of thin-film magnets at arbitrarily designatable locations, with nanoscale spatial resolution. We employ nano-indentation to induce the leakage of stray fields from the materials and use nano-diamond magnetometers to measure them. We apply the method to iron thin films and determine the intrinsic magnetization in the bulk of the materials. This work provides direct access to the intrinsic magnetic properties of thin-film and low-dimensional materials, as well as a method to study the mechanical effects on magnetization in nanomaterials.