Dimensionality-Changing Transition from a Non-Fermi Liquid to a Spin-Solid in a Multichannel Kondo Lattice

Abstract:
              A multichannel Kondo system, where a single quantum spin couples to multiple channels of an electronic bath, provides one of the simplest examples of a zero-dimensional non-Fermi liquid. It is natural to ask: what happens when an extensive number of such systems are coupled together? A simple renormalization group argument implies that in a chain of SU(N) multichannel quantum systems, where each spin is coupled to its own bath of K channels, the individual spins dynamically decouple at low energy when N >K, resulting in a `sliding' non-Fermi liquid. Using Quantum Monte Carlo (QMC) simulations, we find evidence of a continuous, `dimensionality-changing' phase transition out of this non-Fermi liquid into a valence bond solid phase as the intersite coupling is increased. Remarkably, at the critical point, correlations exhibit a power-law behavior even along the direction in which the spins are coupled, indicating the breakdown of dynamical decoupling at the transition. We also develop an RG scheme to understand the universal aspects of this transition.
            TechnicalInfo:
              Processed data used for generating figures in the manuscript: Simon Martin, Marcin Raczkowski, Fakher F. Assaad, and Tarun Grover " Dimensionality-Changing Transition from a Non-Fermi Liquid to a Spin-Solid in a Multichannel Kondo Lattice" arXiv:2510.19937 (2025)
            TechnicalRemarks:
              The data are organized in directories corresponding to the figure numbers in the publication. Each directory contains subdirectories with a gnuplot script (*.gnu), including explicit paths to the data, which can be used to reproduce the figure or its individual panels.
            Other:
              The authors gratefully acknowledge the Gauss Centre for Supercomputing e.V. (www.gauss-centre.eu) for funding this project by providing computing time on the GCS Supercomputer SUPERMUC-NG at Leibniz Supercomputing Centre (www.lrz.de) as well as through the John von Neumann Institute for Computing (NIC) on the GCS Supercomputer JUWELS at the J\"ulich Supercomputing Centre (JSC). We also gratefully acknowledge the scientific support and HPC resources provided by the Erlangen National High Performance Computing Center (NHR@FAU) of the Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) under NHR project 80069 provided by federal and Bavarian state authorities. NHR@FAU hardware is partially funded by the German Research Foundation (DFG) through grant 440719683. F.F.A. acknowledges financial support from the German Research Foundation (DFG) under the grant AS 120/16-1 (Project number 493886309) that is part of the collaborative research project SFB QMS funded by the Austrian Science Fund (FWF) F 86. M. R. acknowledges funding from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), Project No. 332790403 as well as the W\"urzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147, Project ID 390858490). T.G. is supported by the National Science Foundation under Grant No. DMR-2521369.
            

Tags: multichannel-kondo-dot, non-fermi-liquid, quantum-monte-carlo, renormalization-group, valence-bond-solid
Organization: open.bydata