Time-resolved circular dichroism of excitonic systems: theory and experiment on an exemplary squaraine polymer.

ABSTRACT: Experimental and theoretical foundations for femtosecond time-resolved circular dichroism (TRCD) spectroscopy of excitonic systems are presented. In this method, the system is pumped with linearly polarized light and the signal is defined as the difference between the transient absorption spectrum probed with left and with right circularly polarized light. We present a new experimental setup with a polarization grating as key element to generate circularly polarized pulses. Herein the positive (negative) first order of the diffracted light is left-(right-)circularly polarized and serves as a probe pulse in a TRCD experiment. The grating is capable of transferring ultrashort broadband pulses ranging from 470 nm to 720 nm into two separate beams with opposite ellipticity. By applying a speci

SUBMITTER: Ress L 

PROVIDER: S-EPMC10498725 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature