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arXiv · 2302.09701

Matrix Product Study of Spin Fractionalization in the 1D Kondo Insulator

Jing Chen·E. Miles Stoudenmire·Yashar Komijani·Piers Coleman
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Abstract

The Kondo lattice is one of the classic examples of strongly correlated electronic systems. We conduct a controlled study of the Kondo lattice in one dimension, highlighting the role of excitations created by the composite fermion operator. Using time-dependent matrix-product-state methods we compute various correlation functions and contrast them with both large-N mean-field theory and the strong-coupling expansion. We show that the composite fermion operator creates long-lived, charge-e and spin-1/2 excitations, which cover the low-lying single-particle excitation spectrum of the system. Furthermore, spin excitations can be thought to be composed of such fractionalized quasi-particles with a residual interaction which tend to disappear at weak Kondo coupling.

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Jing Chen, E. Miles Stoudenmire, Yashar Komijani, Piers Coleman. 2023-02-20. Matrix Product Study of Spin Fractionalization in the 1D Kondo Insulator. https://doi.org/10.1103/physrevresearch.6.023227

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