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arXiv · 2003.09104

Quantum Fluctuations in the Non-Fermi Liquid System CeCo$_{2}$Ga$_{8}$ Investigated Using $\mu$SR

A. Bhattacharyya·D. T. Adroja·J. S. Lord·L. Wang·Y. Shi·K. Panda·H. Luo·A. M. Strydom
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Abstract

Reduced dimensionality offers a crucial information in deciding the type of the quantum ground state in heavy fermion materials. Here we have examined stoichiometric CeCo$_{2}$Ga$_{8}$ compound, which crystallizes in a quasi-one-dimensional crystal structure with Ga-Ce-Co chains along the $c$-axis. The low-temperature behavior of magnetic susceptibility ($\chi\sim-\ln T$), heat capacity ($C_p/T\sim-\ln T$), and resistivity ($\rho\sim T^{n}$) firmly confirm the non-Fermi liquid ground state of CeCo$_{2}$Ga$_{8}$. We studied the low-energy spin dynamics of CeCo$_{2}$Ga$_{8}$ compound utilizing zero field (ZF-) and longitudinal field (LF-) muon spin relaxation ($\mu$SR) measurements. ZF-$\mu$SR measurement reveals the absence of long-range magnetic ordering down to 70 mK, and interestingly below 1 K, the electronic relaxation rate sharply rises, intimating the appearance of low energy quantum spin fluctuations in CeCo$_{2}$Ga$_{8}$.

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A. Bhattacharyya, D. T. Adroja, J. S. Lord, L. Wang, Y. Shi, K. Panda, H. Luo, A. M. Strydom. 2020-03-20. Quantum Fluctuations in the Non-Fermi Liquid System CeCo$_{2}$Ga$_{8}$ Investigated Using $\mu$SR. https://doi.org/10.1103/physrevb.101.214437

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