Physical Chemistry Seminar: Professor Scott Cushing, California Institute of Technology
About the Seminar
From Batteries to Photoelectrochemistry: Exploring Ultrafast Phenomena with Electrons, X-rays, and Entangled Photons
The Cushing lab focuses on ultrafast instrumentation building that ranges from tabletop X-rays, entangled photon spectroscopy, ultrafast TEM/EELS, to new forms of battery spectroscopy. In this talk, I will give a brief introduction to our research areas, mentioning the increasingly “null” space explored with entangled photons, and then focus on two of the techniques – table top X-ray spectroscopy and our newly created laser-driven ultrafast impedance method. First, we use transient X-ray techniques to element-specifically explore complex photodynamics in solar to fuel and other solid-state systems. The ultrafast X-ray pulses measure a mix of electronic and structural dynamics, and using our excited state Bethe-Salpeter equation approach, we can extract everything from time-resolved electron and hole energies, defect state occupations, phonon and polaron modes, and transport in multi-layer junctions. New examples include measuring a lattice’s coherent response to polaron formation and dynamic localization in superatomic crystals. Second, we use our newly developed, laser-driven ultrafast impedance method to investigate the ion hopping Hamiltonian of superionic conductors. Picosecond temporal and spectral correlations differentiate electron-ion, electron-phonon, and even potentially ion-ion interactions. Follow up transient XUV studies can then give an atomistic view of how material parameters control solid-state electrolyte and electrode performance.
About the Speaker
Scott Cushing is an Assistant Professor at Caltech with a multidisciplinary background spanning Chemistry, Materials Science, and Physics. His research focuses on the creation of new scientific instrumentation that can translate quantum phenomena to practical devices and applications. The Cushing lab is currently pioneering the use of attosecond x-ray, time-resolved TEM-EELS, and ultrafast beams of entangled photons for a range of microscopy and spectroscopy applications. Scott has been awarded DOE, AFOSR, Rose Hill, Cottrell, W.M. Keck, and ACS related Early Career awards. Scott has published over 60 papers that have been cited over 8,000 times. Scott holds multiple patents, some of which have led to start-up companies.