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Topological Transition in the Fermi Surface of Cuprate Superconductors in the Pseudogap Regime

C. M. Varma·Lijun Zhu
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Abstract

The angle-resolved photoemission spectroscopy studies on cuprates in the pseudogap region reveal an extraordinary topological transition in which the ground state changes from one with a normal Fermi surface to one with four Fermi points. Such a state is not possible without some symmetry breaking, which allows interference between one-particle basis states that is normally forbidden. We also show that the experimental results are quantitatively given without any free parameters by a theory and discuss the implications of the results.

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C. M. Varma, Lijun Zhu. 2007-05-01. Topological Transition in the Fermi Surface of Cuprate Superconductors in the Pseudogap Regime. https://doi.org/10.1103/physrevlett.98.177004

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