Revealing intrinsic domains and fluctuations of moir\'e magnetism by a wide-field quantum microscope

TL;DR

This study employs wide-field quantum microscopy to image and analyze the intrinsic moiré magnetic domains and spin fluctuations in twisted double trilayer CrI3, revealing the spatial characteristics of moiré magnetism.

Contribution

It introduces a quantum microscopy approach to directly visualize moiré magnetic domains and spin fluctuations in twisted 2D magnets, advancing understanding of their magnetic phases.

Findings

Intrinsic moiré domains of opposite magnetizations are observed.

Spin fluctuations show little spatial variation on mesoscopic scales.

Moiré magnetism is influenced by stacking and lattice interactions.

Abstract

Moir\'e magnetism featured by stacking engineered atomic registry and lattice interactions has recently emerged as an appealing quantum state of matter at the forefront condensed matter physics research. Nanoscale imaging of moir\'e magnets is highly desirable and serves as a prerequisite to investigate a broad range of intriguing physics underlying the interplay between topology, electronic correlations, and unconventional nanomagnetism. Here we report spin defect-based wide-field imaging of magnetic domains and spin fluctuations in twisted double trilayer (tDT) chromium triiodide CrI3. We explicitly show that intrinsic moir\'e domains of opposite magnetizations appear over arrays of moir\'e supercells in low-twist-angle tDT CrI3. In contrast, spin fluctuations measured in tDT CrI3 manifest little spatial variations on the same mesoscopic length scale due to the dominant driving force of intralayer exchange interaction. Our results enrich the current understanding of exotic magnetic phases sustained by moir\'e magnetism and highlight the opportunities provided by quantum spin sensors in probing microscopic spin related phenomena on two-dimensional flatland.