Real-Time Observation of Cuprates Structural Dynamics by Ultrafast Electron Crystallography
Figure 10
Temperature dependence and phase diagram. (a) Fluence dependence of the intensity decay along the (010) direction of optimally doped Bi2212. In the inset, the fluence dependence of the overall time constant of the decay, obtained from a simple exponential fit (filled black symbols), is shown together with the time constant associated to the electron-phonon coupling time (empty black symbols), obtained from Figure 10(b). (b) Fluence dependence of the derivative of the intensity decay along (010) in optimally doped Bi2212. The characteristic time related to the electron-phonon coupling process is estimated from the minimum in these curves (open black symbols in the inset of Figure 10(a). (c) Lattice-equilibrium temperature dependence of the time constant for both polarizations in all samples. (d) The doping dependence of the coupling constant (λ) along the and directions in Bi2212 (blue and red dots, resp.) and its anisotropy ( between the two directions; black solid line), as well as λ along the and directions in Bi2223 (green and orange dots, resp.) and the extrapolated anisotropy (black dashed line). A qualitative sketch of the upper critical field and Cooper-pair coherence length (green and violet lines) is also shown.
