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Valence Bond Solids and Their Quantum Melting in Hard-Core Bosons on the Kagome Lattice

S. V. Isakov·S. Wessel·R. G. Melko·K. Sengupta·Yong Baek Kim
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Abstract

Using large scale quantum Monte Carlo simulations and dual vortex theory we analyze the ground state phase diagram of hard-core bosons on the kagome lattice with nearest neighbor repulsion. In contrast to the case of a triangular lattice, no supersolid emerges for strong interactions. While a uniform superfluid prevails at half-filling, two novel solid phases emerge at densities $ρ=1/3$ and $ρ=2/3$. These solids exhibit an only partial ordering of the bosonic density, allowing for local resonances on a subset of hexagons of the kagome lattice. We provide evidence for a weakly first-order phase transition at the quantum melting point between these solid phases and the superfluid.

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S. V. Isakov, S. Wessel, R. G. Melko, K. Sengupta, Yong Baek Kim. 2006-07-28. Valence Bond Solids and Their Quantum Melting in Hard-Core Bosons on the Kagome Lattice. https://doi.org/10.1103/physrevlett.97.147202

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