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DOE OSTI Β· 2589820

Two-channel multi-impurity Kondo model: RKKY-induced criticality

Tsvelik, A. M. [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:000000027478670X)Β·Kotliar, G. [Rutgers Univ., Piscataway, NJ (United States)]
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Abstract

We show that the Ruderman-Kittel-Kasua-Yoisida interaction between overscreened spins in two-channel Kondo impurity systems is a relevant perturbation when the number of impurities N is greater than 3 driving the system to a new quantum critical point with anomalous dimensions $\frac{1}{(𝑁+1)}$ for the spin operator and the Sommerfeld coefficient of the specific heat scales as 𝛾 ∼ 𝑇 βˆ’$\frac{3}{𝑁+1}$ . The critical point universal properties are relevant to many strong correlation problems, such as impurity placed in a Majorana metal and the multichannel Kondo lattice model of heavy fermion materials. In conclusion, we discuss relevance of our results for cluster DMFT studies of quantum criticality.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYHeavy-fermion systemsQuantum many-body systemsStrongly correlated systems

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Tsvelik, A. M. [Brookhaven National Laboratory (BNL), Upton, NY (United States)] (ORCID:000000027478670X), Kotliar, G. [Rutgers Univ., Piscataway, NJ (United States)]. 2025-09-11. Two-channel multi-impurity Kondo model: RKKY-induced criticality. https://doi.org/10.1103/ty27-vl8n

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