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arXiv · 1403.7467

Time- and Momentum-resolved Gap Dynamics in Bi2Sr2CaCu2O8+delta

Christopher L. Smallwood·Wentao Zhang·Tristan L. Miller·Chris Jozwiak·Hiroshi Eisaki·Dung-Hai Lee·Alessandra Lanzara
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Abstract

We use time- and angle-resolved photoemission spectroscopy to characterize the dynamics of the energy gap in superconducting Bi2Sr2CaCu2O8+delta (Bi2212). Photoexcitation drives the system into a nonequilibrium pseudogap state: Near the Brillouin zone diagonal (inside the normal-state Fermi arc), the gap completely closes for a pump fluence beyond F = 15 μJ/cm^2; toward the Brillouin zone face (outside the Fermi arc), it remains open to at least 24 μJ/cm^2. This strongly anisotropic gap response may indicate multiple competing ordering tendencies in Bi2212. Despite these contrasts, the gap recovers with relatively momentum-independent dynamics at all probed momenta, which shows the persistent influence of superconductivity both inside and outside the Fermi arc.

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Christopher L. Smallwood, Wentao Zhang, Tristan L. Miller, Chris Jozwiak, Hiroshi Eisaki, Dung-Hai Lee, Alessandra Lanzara. 2014-03-28. Time- and Momentum-resolved Gap Dynamics in Bi2Sr2CaCu2O8+delta. https://doi.org/10.1103/physrevb.89.115126

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