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arXiv · 2203.04104

A solvable 3D Kondo lattice exhibiting odd-frequency pairing and order fractionalization

Piers Coleman·Aaditya Panigrahi·Alexei Tsvelik
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Abstract

The Kondo lattice model plays a key role in our understanding of quantum materials, but a lack of small parameters has posed a long-standing problem. We present a 3 dimensional S= 1/2 Kondo lattice model describing a spin liquid within an electron sea. Strong correlations in the spin liquid are treated exactly, enabling a controlled analytical approach. Like a Peierls or BCS phase, a logarithmically divergent susceptibility leads to an instability into a new phase at arbitrarily small Kondo coupling. Our solution captures a plethora of emergent phenomena, including odd-frequency pairing, pair density wave formation and order fractionalization. The ground-state state is a pair density wave with a fractionalized charge e, S = 1/2 order parameter, formed between electrons and Majorana fermions.

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Piers Coleman, Aaditya Panigrahi, Alexei Tsvelik. 2022-03-08. A solvable 3D Kondo lattice exhibiting odd-frequency pairing and order fractionalization. https://doi.org/10.1103/physrevlett.129.177601

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