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Quantum phases in a doped Mott insulator on the Shastry-Sutherland lattice

Jun Liu·Nandini Trivedi·Yongbin Lee·B. N. Harmon·Joerg Schmalian
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Abstract

We propose the projected BCS wave function as the ground state for the doped Mott insulator SrCu2(BO3)2 on the Shastry-Sutherland lattice. At half filling this wave function yields the exact ground state. Adding mobile charge carriers, we find a strong asymmetry between electron and hole doping. Upon electron doping an unusual metal with strong valence bond correlations forms. Hole doped systems are d-wave RVB superconductors in which superconductivity is strongly enhanced by the emergence of inhomogeneous plaquette bond order.

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Jun Liu, Nandini Trivedi, Yongbin Lee, B. N. Harmon, Joerg Schmalian. 2007-02-05. Quantum phases in a doped Mott insulator on the Shastry-Sutherland lattice. https://doi.org/10.1103/physrevlett.99.227003

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