Simulating neutrino oscillations on a superconducting qutrit

Fault-tolerant quantum computers promise to provide direct simulations for neutrino oscillations in classically intractable scenarios. In today noisy quantum hardware, encoding neutrino in a multi-qubit system requires redundant basis and tricky entangling gates. We study a qutrit encoding for a three-flavor neutrino with the PMNS matrix and time evolution expressed in terms of single qutrit gates. The qutrit is tuned up from the multi-level structure of a IBM superconducting transmon. High-fidelity gate control and readout are engineered using Qiskit Pulse by programming microwave pulses. Our simulation results align well with analytical calculations in three oscillation cases: in vacuum, with CP-violation, and in interaction with matter.