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Pulsed reset protocol for fixed-frequency superconducting qubits

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 نشر من قبل Daniel Egger
 تاريخ النشر 2018
  مجال البحث فيزياء
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Improving coherence times of quantum bits is a fundamental challenge in the field of quantum computing. With long-lived qubits it becomes, however, inefficient to wait until the qubits have relaxed to their ground state after completion of an experiment. Moreover, for error-correction schemes it is import to rapidly re-initialize ancilla parity-check qubits. We present a simple pulsed qubit reset protocol based on a two-pulse sequence. A first pulse transfers the excited state population to a higher excited qubit state and a second pulse into a lossy environment provided by a low-Q transmission line resonator, which is also used for qubit readout. We show that the remaining excited state population can be suppressed to $2.2pm0.8%$ and utilize the pulsed reset protocol to carry out experiments at enhanced rates.



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