Development and application of ultrafast circular dichroism spectroscopy techniques

Chirality hold broad applications in life sciences, quantum devices, and various other areas. Traditionally, molecular chirality can be characterized by using steady-state circular dichroism spectroscopy. However, the techniques that can characterize excited state chirality are progressively capturing the public interest as it can provide the dynamic information for chirality generation and transfer. In this review, we focus on the theoretical background and the developmental history of femtosecond time-resolved circular dichroism spectroscopy (TR-CD) techniques around the world. Additionally, we provide examples to showcase the utility of these techniques in the analysis of the dynamical molecular chemical structures, the investigation of molecular chirality generation, and the detection of electron spin dynamics in semiconductor quantum dots.