Population transfer in a superconducting qutrit via shortcut to adiabaticity with optimized drivings

Abstract

An efficient scheme is proposed for implementing fast population transfer in a superconducting qutrit via shortcut to adiabaticity (STA) with optimized drivings. An artificial atom of Cooper-pair box, having sufficient level anharmonicity, resonantly interacts with two classical microwave drivings. At two-photon resonance, the dynamical behavior of the qutrit can be described by a two-state system. By the technique of STA of counterdiabatic driving, the non-adiabatic coupling between two eigenstates can be nullified. Without increasing the number of applied drivings, we can implement the target state transfer only by modifying two original Gaussian-type pulses. Compared with the pulses required by the invariant-based operation, the modified pulses have the time profiles that are more accessible in experiment. With the available decoherence rates, high-fidelity population transfer can be obtained numerically. The strategy could offer a promising avenue towards optimized control over superconducting qutrits experimentally.