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arXiv · 2408.02892

Local excitation of kagome spin ice magnetism in HoAgGe seen by scanning tunneling microscopy

Hanbin Deng·Tianyu Yang·Guowei Liu·Lu Liu·Lingxiao Zhao·Wu Wang·Tiantian Li·Wei Song·Titus Neupert·Xiang-Rui Liu·Jifeng Shao·Y. Y. Zhao·Nan Xu·Hao Deng·Li Huang·Yue Zhao·Liyuan Zhang·Jia-Wei Mei·Liusuo Wu·Jiaqing He·Qihang Liu·Chang Liu·Jia-Xin Yin
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Abstract

The kagome spin ice can host frustrated magnetic excitations by flipping its local spin. Under an inelastic tunneling condition, the tip in a scanning tunneling microscope can flip the local spin, and we apply this technique to kagome metal HoAgGe with a long-range ordered spin ice ground state. Away from defects, we discover a pair of pronounced dips in the local tunneling spectrum at symmetrical bias voltages with negative intensity values, serving as a striking inelastic tunneling signal. This signal disappears above the spin ice formation temperature and has a dependence on the magnetic fields, demonstrating its intimate relation with the spin ice magnetism. We provide a two-level spin-flip model to explain the tunneling dips considering the spin ice magnetism under spin-orbit coupling. Our results uncover a local emergent excitation of spin ice magnetism in a kagome metal, suggesting that local electrical field induced spin flip climbs over a barrier caused by spin-orbital locking.

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Hanbin Deng, Tianyu Yang, Guowei Liu, Lu Liu, Lingxiao Zhao, Wu Wang, Tiantian Li, Wei Song, Titus Neupert, Xiang-Rui Liu, Jifeng Shao, Y. Y. Zhao, Nan Xu, Hao Deng, Li Huang, Yue Zhao, Liyuan Zhang, Jia-Wei Mei, Liusuo Wu, Jiaqing He, Qihang Liu, Chang Liu, Jia-Xin Yin. 2024-08-06. Local excitation of kagome spin ice magnetism in HoAgGe seen by scanning tunneling microscopy. https://doi.org/10.1103/physrevlett.133.046503

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