Abstract
Developing fast and accurate control and readout techniques is an important challenge in quantum information processing with semiconductor qubits. Here, we study the dynamics and the coherence properties of a GaAs/AlGaAs double quantum dot charge qubit strongly coupled to a frequency-tunable high-impedance resonator. We drive qubit transitions with synthesized microwave pulses and perform qubit readout through the state-dependent frequency shift imparted by the qubit on the dispersively coupled resonator. We perform Rabi oscillation, Ramsey fringe, energy relaxation, and Hahn-echo measurements and find significantly reduced decoherence rates down to corresponding to coherence times of up to for charge states in gate-defined quantum dot qubits. We realize Rabi pulses of width down to .
- Received 14 November 2017
- Revised 31 January 2019
DOI:https://doi.org/10.1103/PhysRevLett.122.206802
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