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arXiv · 2503.06761

Sensing Spin Systems with a Transmission Electron Microscope

Antonín Jaroš·Michael S. Seifner·Johann Toyfl·Benjamin Czasch·Isobel C. Bicket·Philipp Haslinger
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Abstract

We present a novel method that combines spin resonance spectroscopy with transmission electron microscopy (TEM), enabling localized in-situ detection of microwave (MW)-driven spin excitations. Our approach utilizes continuous wave MW excitation at GHz frequencies, while employing the free-space electron beam as a signal receiver to sense spin precession. Spin state polarization is achieved via the magnetic field of the TEM's polepiece, while a custom-designed microresonator integrated into a TEM sample holder drives spin transitions and modulates the electron beam. This modulation enables phase-locked detection with picosecond temporal resolution, allowing the isolation of spin precession contributions to the electron beam deflection with a sensitivity of $\sim 280$ prad. The presented technique lays foundations for the MW spectroscopic in-situ exploration of spin dynamics at the nanoscale.

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Antonín Jaroš, Michael S. Seifner, Johann Toyfl, Benjamin Czasch, Isobel C. Bicket, Philipp Haslinger. 2025-03-09. Sensing Spin Systems with a Transmission Electron Microscope. https://arxiv.org/abs/2503.06761

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