Time-Resolved Measurements of Energy Transport in a System of Coupled Superconducting Qubits Inspired by Simulations of Photosynthetic Processes

Engineered quantum systems have recently found application as a test-bed for answering open questions about energy transport in complex open quantum systems such as photosynthetic systems. Using a circuit incorporating three superconducting transmon qubits, we simulate energy transport with electron-phonon interactions, where we emulate longitudinal coupling to different types of phononic baths by applying engineered flux noise to the qubits. Previously, we considered the effects of noise on energy transport efficiency in steady-state measurements under continuous driving [1]. To study the transport of single photons, we now switch to pulsed excitations and time-resolved measurements. We verify the quantum nature of the excitations transported through the system in anti-bunching measurements, showing second-order correlation functions with g⁽²⁾(0) < 0.05, observe coherent oscillations of the emitted power indicative of static coherence, and study the efficiency of transport as a function of noise type.
[1] A. Potočnik et al., Nat. Comm. 9, 904 (2018)