Transient reflectivity changes of β-ZnP2 exciton bands by pump–probe spectroscopy using a femtosecond laser

Slow dephasing and local field effects of exciton–biexciton transition in detected by femtosecond degenerate four-wave mixing

“…The biexciton fluorescence spectrum was reported to have an asymmetric line shape with a tail to lower energy side, which is caused by the thermal distribution of the biexciton in its dispersion curve. The characteristics we observed are consistent with our recent observation of the very sharp spectrum at 1.550 eV in the measurement of femtosecond transient reflectivity changes for the same bÀZnP 2 sample reported elsewhere [24].…”

“…The bÀZnP 2 sample and experimental setup in the present study were almost the same as those used in our previous papers [23,24]. Single crystals of monoclinic bÀZnP 2 were grown from the vapor phase with the optical flat surface of a bc face.…”