Observation of wave-packet branching through an engineered conical intersection

Speaker: Chris Wang, Yale

Date: Jul 14, 2022 10:00 am

Location: PSC 2136
https://umd.zoom.us/j/7984811536

Abstract:

Analog quantum simulators have the potential to provide new insight towards naturally occurring phenomena beyond the capabilities of classical computers in the near term. Incorporating controllable dissipation as a resource enables simulation of a wider range of out-of-equilibrium processes such as chemical reactions. In this talk, I will describe an experiment where we operate a hybrid qubit-oscillator circuit quantum electrodynamics processor and use it to model nonadiabatic molecular reaction dynamics through a so-called conical intersection. We identify dephasing of the electronic qubit as the mechanism that drives molecular wave-packet branching along the reactive coordinate in our model. We directly observe enhanced branching when the wave-packet passes through the conical intersection. Thus, the forces that influence a chemical reaction can be viewed from the perspective of measurement in quantum mechanics — there is an effective measurement induced dephasing rate that depends on the position of the wave-packet relative to the conical intersection. Our experiment set the groundwork for more complex simulations of chemical dynamics, offering deeper insight into the role of dissipation in determining macroscopic quantities of interest such as the quantum yield of a chemical reaction.