Project supported by the Ministry of Science and Technology of China (Grant Nos. 2016YFA0300504 and 2017YFA0302904) and the National Natural Science Foundation of China (Grant Nos. 11474357, 11774419, 11604383, and 11704401). Y. Y. was supported by the Scientific Equipment Development Project of Chinese Academy of Sciences (Grant No. YJKYYQ20170027).
Jin Feng1, Yang Yang2, Zhang An-Min1, Ji Jian-Ting1, 2, Zhang Qing-Ming1, 2, 3, †
(color online) (a) Steady-state Raman spectra of Bi2Sr2CaCu2O8+δ in B1g geometry (in Porto notation z(xy)z, where z is perpendicular to the CuO planes) at 10 and 300 K. A gap opens below 250 cm−1 (blue area) and a pair-breaking peak appears around 420 cm−1 (red area). (b), (c) Temporal evolution of time-resolved differential Raman spectra at 10 K in B1g geometry. Three differential spectra at three delay times are shown in panel (b), while a contour plot consisting of 12 differential Raman spectra is presented in panel (c). The dashed line separates pair-breaking peak into two energy regions that have distinct characteristic behaviors. The change in intensity is colored. There is a transfer of spectral weight from high to low energies after 1 ps. Reprinted with permission from Ref. [55], copyright 2009 by the American Physical Society.
