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Updated: Jul 14, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Probing GHz Spin Dynamics across Magnetic Phase Transitions in CrCl3 Nanoflakes Using Nitrogen-Vacancy Microscopy
Benjamin Hammons1, Jitender Kumar1, Sehrish Iqbal1
1Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska68588, United States.
ACS Nano
|July 13, 2026
Summary
Chromium chloride (CrCl3) nanoflakes show intense spin fluctuations in the ferromagnetic state, impacting their use in 2D magnonics. These dynamics are strongest in the ferromagnetic regime and change significantly across magnetic phase transitions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Sensing
Background:
- Layered van der Waals (vdW) magnets like CrCl3 are promising for nanoscale magnetic phenomena.
- Tuning magnetic properties via interfaces and external stimuli is key for spintronic applications.
Purpose of the Study:
- Investigate the spin dynamics of CrCl3 nanoflakes near magnetic phase transitions.
- Understand the role of spin fluctuations in the ferromagnetic regime for magnonic applications.
Main Methods:
- Utilized cryogenic diamond quantum sensing microscopy with nitrogen-vacancy (NV) centers.
- Measured optically detected magnetic resonance, Rabi oscillations, and spin-lattice relaxation time (T1).
- Performed broadband ferromagnetic resonance spectroscopy on CrCl3 crystals.
Main Results:
- Observed reduced NV spin resonance contrast and collapsed Rabi oscillations in the ferromagnetic regime.
- Reported a 2-orders-of-magnitude enhancement in relaxation rate (Γ1 = 1/T1), indicating gigahertz spin fluctuations.
- Ferromagnetic resonance spectroscopy showed 4-15 GHz frequencies and a ~24 mT line width.
Conclusions:
- Magnetic noise is strongest in the ferromagnetic regime of CrCl3, significantly impacting NV center relaxation.
- A phenomenological model successfully reproduced temperature-dependent relaxation by considering various magnetic fluctuation channels.
- Results are vital for advancing 2D magnonics and hybrid quantum-magnon systems using CrCl3.
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