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arXiv · 1906.01740

Magnetic field-tuned quantum criticality in a Kondo insulator

Satya K. Kushwaha·Mun K. Chan·Joonbum Park·S. M. Thomas·Eric D. Bauer·J. D. Thompson·F. Ronning·Priscila F. S. Rosa·Neil Harrison
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Abstract

Kondo insulators are predicted to undergo an insulator-to-metal transition under applied magnetic field, yet the extremely high fields required to date have prohibited a comprehensive investigation of the nature of this transition. Here we show that Ce3Bi4Pd3 provides an ideal platform for this investigation, owing to the unusually small magnetic field of B ~ 11 T required to overcome its Kondo insulating gap. Above Bc, we find a magnetic field-induced Fermi liquid state whose characteristic energy scale T_FL collapses near Bc in a manner indicative of a magnetic field-tuned quantum critical point. A direct connection is established with the process of Kondo singlet formation, which yields a broad maximum in the magnetic susceptibility as a function of temperature in weak magnetic fields that evolves progressively into a sharper transition at Bc as T -> 0.

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Satya K. Kushwaha, Mun K. Chan, Joonbum Park, S. M. Thomas, Eric D. Bauer, J. D. Thompson, F. Ronning, Priscila F. S. Rosa, Neil Harrison. 2019-06-04. Magnetic field-tuned quantum criticality in a Kondo insulator. https://doi.org/10.1038/s41467-019-13421-w

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