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arXiv · 1712.01854

Exact solution of a two-species quantum dimer model for pseudogap metals

Johannes Feldmeier·Sebastian Huber·Matthias Punk
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Abstract

We present an exact ground state solution of a quantum dimer model introduced in Ref.[1], which features ordinary bosonic spin-singlet dimers as well as fermionic dimers that can be viewed as bound states of spinons and holons in a hole-doped resonating valence bond liquid. Interestingly, this model captures several essential properties of the metallic pseudogap phase in high-$T_c$ cuprate superconductors. We identify a line in parameter space where the exact ground state wave functions can be constructed at an arbitrary density of fermionic dimers. At this exactly solvable line the ground state has a huge degeneracy, which can be interpreted as a flat band of fermionic excitations. Perturbing around the exactly solvable line, this degeneracy is lifted and the ground state is a fractionalized Fermi liquid with a small pocket Fermi surface in the low doping limit.

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Johannes Feldmeier, Sebastian Huber, Matthias Punk. 2017-12-05. Exact solution of a two-species quantum dimer model for pseudogap metals. https://doi.org/10.1103/physrevlett.120.187001

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