Quantum phase transition in a random-tiling model

D. K. Sunko

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Quantum phase transition in a random-tiling model

D. K. Sunko

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Abstract

The analogue of a Mott-Hubbard transition is discussed, which appears at an incommensurate filling in a model of a two-dimensional plane, randomly tiled with CuO_4 `molecules', simulating the copper-oxide planes of high-T_c superconductors. It is shown to be a quantum phase transition, which can be crossed either in doping, at a fixed hopping overlap t, or in t, when the doping is fixed in a certain range below half-filling. It is first-order, closely analogous to a liquid-gas transition.

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D. K. Sunko. 2000-05-10. Quantum phase transition in a random-tiling model. https://arxiv.org/abs/cond-mat/0005170

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