Novel noncollinear antiferromagnets with spontaneous time-reversal symmetry breaking, nontrivial band topology, and unconventional transport properties have received immense research interest over the past decade due to their rich physics and enormous promise in technological applications. One of the central focuses in this emerging field is exploring the relationship between the microscopic magnetic structure and exotic material properties. Here, the nanoscale imaging of both spin-orbit-torque-induced deterministic magnetic switching and chiral spin rotation in noncollinear antiferromagnet Mn3Sn films using nitrogen-vacancy (NV) centers is reported. Direct evidence of the off-resonance dipole-dipole coupling between the spin dynamics in Mn3Sn and proximate NV centers is also demonstrated with NV relaxometry measurements. These results demonstrate the unique capabilities of NV centers in accessing the local information of the magnetic order and dynamics in these emergent quantum materials and suggest new opportunities for investigating the interplay between topology and magnetism in a broad range of topological magnets.
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This content will become publicly available on June 14, 2024
Nanoscale Magnetic Domains in Polycrystalline Mn 3 Sn Films Imaged by a Scanning Single-Spin Magnetometer
Noncollinear antiferromagnets with novel magnetic orders, vanishingly small net
magnetization and exotic spin related properties hold enormous promise for developing next generation,
transformative spintronic applications. A major ongoing research focus of this
community is to explore, control, and harness unconventional magnetic phases of this emergent
material system to deliver state-of-the-art functionalities for modern microelectronics. Here we
report direct imaging of magnetic domains of polycrystalline Mn3Sn films, a prototypical
noncollinear antiferromagnet, using nitrogen-vacancy-based single-spin scanning microscopy.
Nanoscale evolution of local stray field patterns of Mn3Sn samples are systematically investigated
in response to external driving forces, revealing the characteristic “heterogeneous” magnetic
switching behaviors in polycrystalline textured Mn3Sn films. Our results contribute to a
comprehensive understanding of inhomogeneous magnetic orders of noncollinear
antiferromagnets, highlighting the potential of nitrogen-vacancy centers to study microscopic spin
properties of a broad range of emergent condensed matter systems.
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- NSF-PAR ID:
- 10485911
- Publisher / Repository:
- ACS publications
- Date Published:
- Journal Name:
- Nano Letters
- Volume:
- 23
- Issue:
- 11
- ISSN:
- 1530-6984
- Page Range / eLocation ID:
- 5326 to 5333
- Subject(s) / Keyword(s):
- ["quantum sensing, scanning nitrogen-vacancy magnetometry, topological magnets, antiferromagnetic materials"]
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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