Polarization-induced fluorescence modulation in a self-assembled coordination cage-shaped complex

Polarization-induced fluorescence modulation behavior of a self-assembled coordination cage-shaped complex was investigated using femtosecond laser pulses. The variations of the total two-photon-induced fluorescence (TPF) intensity were found to be strongly modulated by different polarized incident lights and tightly dependent on the linearly polarized component of the excited light. The polarization-induced modulation efficiency of the TPF underwent intensity-dependent decrease, which could be attributed to the two-photon-induced excited-state absorption. The nonlinear absorption behavior of the complex was also studied by performing both femtosecond open aperture Z-scan and nonlinear transmission measurements, which help to better understand the intrinsic optical properties of the molecule and portend its practical applications.