# Quantum-mechanical treatment of atomic resolution differential phase contrast imaging of magnetic materials

## TL;DR

This paper uses a quantum-mechanical multislice method to simulate atomic resolution differential phase contrast imaging of magnetic materials, revealing how electric and magnetic fields influence the imaging patterns.

## Contribution

It introduces a quantum-mechanical approach to simulate DPC imaging of magnetic materials, providing insights into the interpretation of magnetic signals at atomic resolution.

## Key findings

- Simulated DPC patterns contain information about electric and magnetic fields.
- The magnetic component matches density functional theory calculations at low thicknesses.
- The momentum transfer in the pattern remains curl-free, affecting interpretation.

## Abstract

Utilizing the Pauli equation based multislice method, introduced in Phys. Rev. Lett. 116, 127203 (2016), we study the atomic resolution differential phase contrast (DPC) imaging on an example of a hard magnet FePt with in-plane magnetization. Simulated center of mass pattern in a scanning transmission electron microscopy (STEM) experiment carries information about both electric and magnetic fields. The momentum transfer remains curl-free, which has consequences for interpretation of the integrated DPC technique. The extracted magnetic component of the pattern is compared to the expected projected microscopic magnetic field as obtained by density functional theory calculation. Qualitative agreement is obtained for low sample thicknesses and a suitable range of collection angles.