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arXiv · 2412.13410

The spin-switch scanning tunneling microscopy: an architecture to probe electron-phonon interactions in the atomic scale

Abstract

On the spin-valve-like ferromagnet/spin glass/ferromagnet (FM/SG/FM) structure, the tunneling current is dominated by resistance switch (RS) instead of the local density of states according to the conventional tunneling theory. Here we show lattice-site dependent RS behaviors in one-quintuple-layer Bi2Te3 deposited on single MnBi2Te4 septuple layer, which comes from the difference in the efficiency of tunneling electrons to induce focused current or phonons at different sites, switching remotely the spin valve by spin-transfer torque or spin-phonon interactions. These lead to the observation of the dynamic 2-state lattice when the tip scans across the surface as well as the ability of scanning tunneling microscope (STM) to reveal atomic-scale features of electron-phonon (EP) interactions. Our work demonstrates the possibility of the spin-switch STM to image lattice-site dependent EP interactions of any materials deposited on the FM/SG/FM structure.

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Dezhi Song, Fuyang Huang, Yu Gao, Jiamin Yao, Haimin Zhang, Haiming Huang, Jun Zhang, Xu-Cun Ma, Qi-Kun Xue, Ye-Ping Jiang. 2024-12-18. The spin-switch scanning tunneling microscopy: an architecture to probe electron-phonon interactions in the atomic scale. https://arxiv.org/abs/2412.13410

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