A Sacrificial Magnet Concept for Field Dependent Surface Science Studies

TL;DR

This paper presents a simple method to incorporate a magnetic field into low-temperature STM by using a sacrificial NdFeB magnet, enabling field-dependent surface studies up to 400 mT with high-temperature cleaning compatibility.

Contribution

The authors introduce a novel, in-situ magnet replacement technique that allows magnetic field integration in STM without permanent magnet retention, suitable for high-temperature cleaning processes.

Findings

Magnetic field characterized by Abrikosov vortex lattice in NbSe2.

Excellent agreement between experimental and simulated magnetic fields.

Magnet can be sacrificially demagnetized and replaced in-situ.

Abstract

We demonstrate a straightforward approach to integrating a magnetic field into a low-temperature scanning tunneling microscope (STM) by adhering an NdFeB permanent magnet to a magnetizable sample plate. To render our magnet concept compatible with high-temperature sample cleaning procedures, we make the irreversible demagnetization of the magnet a central part of our preparation cycle. After sacrificing the magnet by heating it above its Curie temperature, we use a transfer tool to attach a new magnet in-situ prior to transferring the sample into the STM. We characterize the magnetic field created by the magnet using the Abrikosov vortex lattice of superconducting NbSe2. Excellent agreement between the distance dependent magnetic fields from experiments and simulations allows us to predict the magnitude and orientation of magnetic flux at any location with respect to the magnet and the sample plate. Our concept is an accessible solution for field-dependent surface science studies that require fields in the range of up to 400 mT and otherwise detrimental heating procedures.