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arXiv · 1311.4719

Dynamics of broken symmetry nodal and anti-nodal excitations in Bi_{2} Sr_{2} CaCu_{2} O_{8+δ} probed by polarized femtosecond spectroscopy

Y. Toda·F. Kawanokami·T. Kurosawa·M. Oda·I. Madan·T. Mertelj·V. V. Kabanov·D. Mihailovic
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Abstract

The dynamics of excitations with different symmetry is investigated in the superconducting (SC) and normal state of the high-temperature superconductor Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+δ}$ (Bi2212) using optical pump-probe (Pp) experiments with different light polarizations at different doping levels. The observation of distinct selection rules for SC excitations, present in A$_{\rm 1g}$ and B$_{\rm 1g}$ symmetries, and for the PG excitations, present in A$_{\rm 1g}$ and B$_{\rm 2g}$ symmetries, by the probe and absence of any dependence on the pump beam polarization leads to the unequivocal conclusion of the existence of a spontaneous spatial symmetry breaking in the pseudogap (PG) state.

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Y. Toda, F. Kawanokami, T. Kurosawa, M. Oda, I. Madan, T. Mertelj, V. V. Kabanov, D. Mihailovic. 2013-11-19. Dynamics of broken symmetry nodal and anti-nodal excitations in Bi_{2} Sr_{2} CaCu_{2} O_{8+δ} probed by polarized femtosecond spectroscopy. https://doi.org/10.1103/physrevb.90.094513

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