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arXiv · 2209.08672

Control of chiral orbital currents in a colossal magnetoresistance material

Yu Zhang·Yifei Ni·Hengdi Zhao·Sami Hakani·Feng Ye·Lance DeLong·Itamar Kimchi·Gang Cao
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Abstract

Colossal magnetoresistance (CMR) is an extraordinary enhancement of the electric conductivity in the presence of a magnetic field. It is conventionally associated with a field-induced spin polarization, which drastically reduces spin scattering and thus electric resistance. However, ferrimagnetic Mn3Si2Te6 is an intriguing exception to this rule: it exhibits a 7-order-of-magnitude reduction in ab-plane resistivity with a 13-Tesla anisotropy field which occur only when a magnetic polarization is avoided [1]. Here we report an exotic quantum state that is driven by ab-plane chiral orbital currents (COC) flowing along edges of MnTe6 octahedra. The c-axis orbital moments of ab-plane COC couple to the ferrimagnetic Mn spins to drastically increase the ab-plane conductivity (CMR) when an external magnetic field is aligned along the magnetic hard c-axis. Both the COC state and its CMR are extraordinarily susceptible to small DC currents exceeding a critical threshold, and a hallmark of this COC state is an exotic time-dependent, bistable switching mimicking a first-order melting transition. The control of the COC-enabled CMR and bistable switching offers a fundamentally new paradigm for quantum technologies.

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Yu Zhang, Yifei Ni, Hengdi Zhao, Sami Hakani, Feng Ye, Lance DeLong, Itamar Kimchi, Gang Cao. 2022-09-18. Control of chiral orbital currents in a colossal magnetoresistance material. https://doi.org/10.1038/s41586-022-05262-3

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