Exploring Exciton Transport Dynamics Using Spatially Offset Femtosecond Stimulated Raman Spectroscopy

Understanding exciton transport in photovoltaic materials is vital for exploiting their full potential, but there is a lack of research into how molecular structure can be manipulated to tune ultrafast dynamics. Recently, our lab developed spatially offset femtosecond stimulated Raman spectroscopy (SOFSRS) to fill this void. This novel advanced microscopy technique combines the high structural specificity of traditional FSRS with the ability to observe ultrafast dynamics on time and length scales relevant for charge transport behavior. Here, I will discuss recent improvements to this technique to study the role of lattice phonons in exciton transport in crystalline organic materials. Results indicate transport occurs preferentially along the long axis in a pentacene crystal. These results are a promising indication of how SOFSRS can be used to understand transport dynamics in a variety of systems.