Speaker: Francesco Peronaci, International School for Advanced Studies (SISSA)
Date & Time: April 21, 2016, 2:00 - 3:00
Location: Hennings 318
Local Contact: Ilya Elfimov
Intended Audience: Graduate
Motivated by recent ultrafast pump-probe experiments on high-temperature superconductors, we discuss the transient dynamics of a d-wave BCS model after a quantum quench of the interaction parameter. We find that the existence of gap nodes, with the associated nodal quasiparticles, introduces a decay channel which makes the dynamics much faster than in the conventional s-wave model. For every value of the quench parameter, the superconducting gap rapidly converges to a stationary value smaller than the one at equilibrium. Using a sudden approximation for the gap dynamics, we find an analytical expression for the reduction of spectral weight close to the nodes, in qualitative agreement with the experimental results.
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 C. L. Smallwood, W. Zhang, T. L. Miller, C. Jozwiak, H. Eisaki, D-H. Lee, and A. Lanzara, Phys. Rev. B 89, 115126 (2014).