paper

Mode-selective coupling of coherent phonons to the Bi2212 electronic band structure

arXiv:1904.06602 · doi:10.1103/PhysRevLett.122.176403

Abstract

Cuprate superconductors host a multitude of low-energy optical phonons. Using time- and angle-resolved photoemission spectroscopy, we study coherent phonons in BiSrCaYCuO. Sub-meV modulations of the electronic band structure are observed at frequencies of and THz. For the dominant mode at 3.94 THz, the amplitude of the band energy oscillation weakly increases as a function of momentum away from the node. Theoretical calculations allow identifying the observed modes as CuO-derived phonons. The Bi- and Sr-derived modes which dominate Raman spectra in the relevant frequency range are absent in our measurements. This highlights the mode-selectivity for phonons coupled to the near-Fermi-level electrons, which originate from CuO planes and dictate thermodynamic properties.

7 pages, 3 figures

References in corpus (14)

Cited by in corpus (4)