Quantum Imaging of Magnetic Phase Transitions and Spin Fluctuations in Intrinsic Magnetic Topological Nanoflakes

TL;DR

This paper demonstrates nanoscale quantum imaging of magnetic phase transitions and spin fluctuations in MnBi2Te4 (Bi2Te3)n topological nanoflakes using NV centers, revealing fundamental magnetic properties and domain structures.

Contribution

It introduces a novel application of NV center quantum sensing to study magnetic phenomena in topological materials at the nanoscale.

Findings

Nanoscale imaging of magnetic phase transitions.

Observation of spin fluctuations and magnetic domains.

Insights into the interplay between topology and magnetism.

Abstract

Topological materials featuring exotic band structures, unconventional current flow patterns, and emergent organizing principles offer attractive platforms for the development of next-generation transformative quantum electronic technologies. The family of MnBi2Te4 (Bi2Te3)n materials is naturally relevant in this context due to their nontrivial band topology, tunable magnetism, and recently discovered extraordinary quantum transport behaviors. Despite numerous pioneering studies, to date, the local magnetic properties of MnBi2Te4 (Bi2Te3)n remain an open question, hindering a comprehensive understanding of their fundamental material properties. Exploiting nitrogen-vacancy (NV) centers in diamond, we report nanoscale quantum imaging of magnetic phase transitions and spin fluctuations in exfoliated MnBi2Te4 (Bi2Te3)n flakes, revealing the underlying spin transport physics and magnetic domains at the nanoscale. Our results highlight the unique advantage of NV centers in exploring the magnetic properties of emergent quantum materials, opening new opportunities for investigating the interplay between topology and magnetism.