Spin-charge qubit resonance readout in lateral quantum dots

We report on the fabrication and simulation of a lateral quantum dot (QD) designed for coherent electrical manipulation and readout of a two-level spin-charge system. The two-level system involves a slight hybridization of a single electron spin to the QD orbitals. A permanent magnet integrated with high-frequency electrode produces a static slanting magnetic field suitable for voltage controlled single qubit rotations. Resonance frequency and rotation speed are related to device parameters. Response of the nearby quantum point contact charge sensor is modeled for continuous microwave excitation, taking into account parasitic photon-assisted tunneling effects induced by the high-frequency electric field. The model predicts a well-defined resonance in the readout signal associated to driven rotations of the qubit states.