We report the results of femtosecond spectroscopy studies on YBa_(2)Cu_(3)O_(7-x )and PrBa_(2)Cu_(3)O_(7-x )(x=0.1)epitaxial thin films at room temperature.The transient reSectivity signals ΔR(t)in the samples are co...We report the results of femtosecond spectroscopy studies on YBa_(2)Cu_(3)O_(7-x )and PrBa_(2)Cu_(3)O_(7-x )(x=0.1)epitaxial thin films at room temperature.The transient reSectivity signals ΔR(t)in the samples are consistent with a band filliitg model.The relaxation times of ΔR(t)in YBa_(2)Cu_(3)O_(7-x ) increase from less th&n 100 fs to more than Ips with increasing x and with substitution of Pr for Y.These results reveal that in high Tc superconductors decrease of carrier concentration slows down the carrier-phonon coupling.展开更多
基金Supported by the National Center for Research and Development on Superconductivity of China.
文摘We report the results of femtosecond spectroscopy studies on YBa_(2)Cu_(3)O_(7-x )and PrBa_(2)Cu_(3)O_(7-x )(x=0.1)epitaxial thin films at room temperature.The transient reSectivity signals ΔR(t)in the samples are consistent with a band filliitg model.The relaxation times of ΔR(t)in YBa_(2)Cu_(3)O_(7-x ) increase from less th&n 100 fs to more than Ips with increasing x and with substitution of Pr for Y.These results reveal that in high Tc superconductors decrease of carrier concentration slows down the carrier-phonon coupling.