Effect of ac magnetic field on single qubit gate operation in noisy environment

Abstract

Quantum dot-based single spin qubit systems are resilient towards charge noise and are primarily affected by the noise due to magnetic interactions. Qubit interaction with the environment causes relaxation and decoherence of their quantum states. Hyperfine interaction due to spin of nuclei surrounding the electron and phononic interaction due to spin-orbit interaction are the dominant mechanisms through which GaAs-based quantum dot (QD) qubits undergo decoherence. The external control parameters i.e. static and ac magnetic fields are directly related to the decoherence. This limits the range of values of these parameters for which gate operations can be done successfully. In this work, using a single qubit NOT gate operation, we investigate the impact of varying static and ac magnetic fields on decoherence suppression. We report an increment in the usable range of the static magnetic field value with an increase in ac magnetic field strength in low and high static magnetic field regimes.