Heavy fermion metals hosting multipolar local moments set a new stage for exploring exotic spin-orbital entangled quantum phases. In such systems, the quadrupolar Kondo effect serves as the key ingredient in the orbital-driven non-Fermi liquid (NFL) behavior and quantum critical phenomena. The cubic heavy fermion superconductor PrTr2Al20 (Tr: Ti, V) is a prime candidate for realizing the quadrupolar Kondo lattice. Here, we present a systematic study of the NFL phenomena in PrV2Al20 based on magnetoresistance (MR), magnetic susceptibility and specific heat measurements. Upon entering the NFL regime, we observe a universal scaling behavior expected for the quadrupolar Kondo lattice in PrV2Al20, which indicates a prominent role of the quadrupolar Kondo effect in driving the NFL behavior. Deviations from this scaling relation occur below ∼8 K, accompanied by a sign change in the MR and a power-law divergence in the specific heat. This anomalous low-temperature state points to the presence of other mechanisms which are not included in the theory, such as heavy fermion coherence or multipolar quantum critical fluctuations.
@article{arxiv.1907.12483,
title = {Unveiling Quadrupolar Kondo Effect in the Heavy Fermion Superconductor PrV$_2$Al$_{20}$},
author = {Mingxuan Fu and Akito Sakai and Naoki Sogabe and Masaki Tsujimoto and Yosuke Matsumoto and Satoru Nakatsuji},
journal= {arXiv preprint arXiv:1907.12483},
year = {2020}
}