Impurity Effects on the Flux Phase Quantum Critical Point Scenario

E. Cappelluti; R. Zeyher

doi:10.1209/epl/i2000-00175-8

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Impurity Effects on the Flux Phase Quantum Critical Point Scenario

E. Cappelluti·R. Zeyher

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Abstract

Impurity substitution of Zn in La-214 and (Y,Ca)-123 high-T_c superconductors suppresses T_c but does not affect appreciably the onset of the pseudogap phase in the underdoped region nor optimal doping or the position of the inferred quantum critical point. Based on a 1/N expansion of the t-J model we explain these findings as well as the similar dependence on a magnetic field in terms of a quantum critical point scenario where a flux phase causes the pseudogap.

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E. Cappelluti, R. Zeyher. 1999-12-08. Impurity Effects on the Flux Phase Quantum Critical Point Scenario. https://doi.org/10.1209/epl%2Fi2000-00175-8

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