Scatter Plot from Scientific Research

Maximum of the pump-induced change in the MIR electric field Delta E_MIR^max as a function of the pump–probe delay time t_pp for a fixed electro-optic sampling time t_EOS (light-coloured lines; Phi_NIR = 225 microJ cm^-2) recorded at different temperatures T. The data on a logarithmic scale are vertically offset for clarity. The darker-coloured lines represent mono- and biexponential decay fits. For clarity, a ten-point (thirty-point) moving average was applied for delay times smaller (larger) than 20 ps. The dashed lines indicate the isolated fast- and slow-decay components of the fit and highlight the deviation from monoexponential decay at elevated temperatures. Top: density fraction of intralayer and interlayer excitons as a function of t_pp at T = 200 K (dashed lines). The inset in a shows the level scheme of interlayer-like (X_inter) and intralayer-like (X_intra) excitons relative to the continuum (shaded region) and the ground state (GS). Upon excitation by the NIR pulse (yellow arrow), both exciton species can form (dashed arrows) and decay with rates tau_1 and tau_2. Elevated lattice temperatures facilitate the population of X_inter (purple arrow), resulting in a decrease (increase) in the fraction of the short-lived (long-lived) exciton species.

DOI