A Verilog-A superconducting qubit model for co-simulation with control and readout systems in the Cadence Analog Environment

This paper introduces two Verilog-A blocks implemented in the Cadence Analog Environment as testbenches for integrating qubits with the electronics necessary for qubit state manipulation and measurement in circuit-level simulations. These blocks specifically model the control and readout mechanisms of transmon qubits, a type of superconducting qubit, by using key transmon and circuit parameters as inputs. The first block models the XY qubit control mechanism, simulating qubit state manipulation by a microwave driving pulse with adjustable shape, amplitude, and duration. It outputs the qubit state probability and the pulse parameters needed for arbitrary qubit rotations. The second block models the dispersive shift readout mechanism, providing the transient response of the qubit to a reading pulse. This block can determine the qubit state based on the pulse’s amplitude and phase and accounts for noise from the amplification stages. Simulation results using realistic transmon parameters validate the functionality of these Verilog-A blocks.