Simulation of dissipative conical intersection reaction dynamics in a superconducting circuit

Conical intersections (CIs) are ubiquitous features in quantum chemistry where two molecular potential energy surfaces intersect. Characterized by a breakdown of the Born-Oppenheimer approximation, they result in strong hybridization between electronic and nuclear degrees of freedom. CIs enable nonadiabatic transitions between electronic states and, when combined with vibrational damping, may heavily influence outcomes of chemical reactions. Though conventionally investigated through spectroscopic means, it would be desirable to engineer a synthetic CI with tunable control to systematically explore the parameter space. Superconducting circuits have emerged as a powerful platform for simulating quantum systems, possessing a versatile range of controllable interactions and engineered dissipation. In this talk, we report on experimental progress towards simulating a CI Hamiltonian in a circuit with one nonlinear (electronic) and two linear (nuclear) modes. We engineer the system to support two distinct ground states in one of the nuclear coordinates, representing reactant and product configurations. By preparing an excited state and tuning the dissipation, we highlight the competition between coherent evolution and damping in determining the branching ratio of the model reaction.