arXiv 0907.35432009-07-21cond-mat.str-elcond-mat.supr-con

Supersolidity in a Bose-Holstein model

Sanjoy Datta, Sudhakar Yarlagadda

英文摘要：

We derive an effective d-dimensional Hamiltonian for a system of hard-core-bosons coupled to optical phonons in a lattice. At non-half-fillings, a superfluid-supersolid transition occurs at intermediate boson-phonon couplings, while at strong-couplings the system phase separates. We demonstrate explicitly that the presence of next-nearest-neighbor hopping and nearest-neighbor repulsion leads to supersolidity. Thus we present a microscopic mechanism for the homogeneous coexistence of charge-density-wave and superfluid orders.

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