English

Control of chiral orbital currents in a colossal magnetoresistance material

Strongly Correlated Electrons 2022-10-17 v1 Materials Science Quantum Physics

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.

Keywords

Cite

@article{arxiv.2209.08672,
  title  = {Control of chiral orbital currents in a colossal magnetoresistance material},
  author = {Yu Zhang and Yifei Ni and Hengdi Zhao and Sami Hakani and Feng Ye and Lance DeLong and Itamar Kimchi and Gang Cao},
  journal= {arXiv preprint arXiv:2209.08672},
  year   = {2022}
}

Comments

5 figures. The final version of this paper, which is more updated than this version, is to be published in Nature