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arXiv · 1302.0248

Competition between the Pseudogap and Superconducting States of Bi$_{2}$Sr$_{2}$Ca$_{0.92}$Y$_{0.08}$Cu$_{2}$O$_{8+\delta}$ Single Crystals Revealed by Ultrafast Broadband Optical Reflectivity

G. Coslovich·C. Giannetti·F. Cilento·S. Dal Conte·T. Abebaw·D. Bossini·G. Ferrini·H. Eisaki·M. Greven·A. Damascelli·F. Parmigiani
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Abstract

Ultrafast broadband transient reflectivity experiments are performed to study the interplay between the non-equilibrium dynamics of the pseudogap and the superconducting phases in Bi$_{2}$Sr$_{2}$Ca$_{0.92}$Y$_{0.08}$Cu$_{2}$O$_{8+\delta}$. Once superconductivity is established the relaxation of the pseudogap proceeds $\sim$ 2 times faster than in the normal state, and the corresponding transient reflectivity variation changes sign after $\sim$ 0.5 ps. The results can be described by a set of coupled differential equations for the pseudogap and for the superconducting order parameter. The sign and strength of the coupling term suggest a remarkably weak competition between the two phases, allowing their coexistence.

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G. Coslovich, C. Giannetti, F. Cilento, S. Dal Conte, T. Abebaw, D. Bossini, G. Ferrini, H. Eisaki, M. Greven, A. Damascelli, F. Parmigiani. 2013-02-01. Competition between the Pseudogap and Superconducting States of Bi$_{2}$Sr$_{2}$Ca$_{0.92}$Y$_{0.08}$Cu$_{2}$O$_{8+\delta}$ Single Crystals Revealed by Ultrafast Broadband Optical Reflectivity. https://doi.org/10.1103/physrevlett.110.107003

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