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arXiv · 1605.04366

Observation of orbital two-channel Kondo effect in a ferromagnetic L10-MnGa film

L. J. Zhu·G. Woltersdorf·J. H. Zhao
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Abstract

The experimental existence and stability of the quantum criticality point of the two-channel Kondo (2CK) effect displaying exotic non-Fermi liquid physics has been buried in persistent confusion despite the intensive theoretical and experimental efforts in past three decades. Here we report an experimental realization of the two-level system scattering-induced orbital 2CK effect in a ferromagnetic L10-MnGa film, which is signified by a magnetic field-independent resistivity upturn that has a logarithmic and square-root temperature dependence beyond and below the Kondo temperature of ~14.5 K, respectively. Our result not only evidences the robust existence of orbital 2CK effect even in the presence of strong magnetic fields and long-range ferromagnetic ordering but also extends the scope of 2CK host materials from nonmagnetic nanoscale point contacts to diffusive conductors of disordered alloys.

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L. J. Zhu, G. Woltersdorf, J. H. Zhao. 2016-05-14. Observation of orbital two-channel Kondo effect in a ferromagnetic L10-MnGa film. https://doi.org/10.1038/srep34549

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