Thermodynamic evidence for novel quantum criticality in a frustrated metal

Shunichiro Kittaka, Yohei Kono, Suguru Tsuda, Toshiro Takabatake & Toshiro Sakakibara

Apr 23, 2019

Received Date: 16th April 19

Various exotic phases of matter have been discovered near a quantum critical point where magnetic order is suppressed to absolute zero temperature by strong quantum fluctuations. There have remained fundamental questions whether geometrical frustration preventing magnetic long-range order can induce quantum critical phenomena and how novel they are. Here, we employ a magnetic field angle as a tuning parameter and provide thermodynamic evidence for novel quantum criticality not only driven but also augmented by frustration in the quasi-kagome Kondo-lattice CeRhSn. The field-angle-resolved landscape of the entropy reveals the existence of a quantum critical line under a magnetic field, exactly parallel to the quasi-kagome plane. In particular, on this line, we observe a two-step decrease of the entropy accompanied by a qualitative change in the non-Fermi-liquid behavior. These results suggest that a partial release of frustration induces a quantum critical "phase", whose nature is distinctly different from the zero-field one.

Read in full at arXiv.


Nature Communications

Nature Research, Springer Nature