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Updated: May 14, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Feedback control of a solid-state qubit using high-fidelity projective measurement.
D Ristè1, C C Bultink, K W Lehnert
1Kavli Institute of Nanoscience, Delft University of Technology, PO Box 5046, 2600 GA Delft, The Netherlands.
Physical Review Letters
|February 2, 2013
Summary
We demonstrate fast and deterministic qubit reset using feedback control, enabling over 10x faster experiments. This closed-loop control is crucial for quantum error correction and teleportation protocols.
Area of Science:
- Quantum Computing
- Superconducting Qubits
- Quantum Control
Background:
- Superconducting transmon qubits are fundamental building blocks for quantum computers.
- Efficient qubit initialization and control are critical for scalable quantum computation.
Purpose of the Study:
- To demonstrate feedback control for rapid and deterministic qubit reset.
- To enable faster experimental cycles in quantum computing.
Main Methods:
- Utilizing discrete, projective measurement.
- Implementing conditional coherent driving for feedback.
- Applying closed-loop control to superconducting transmon qubits.
Main Results:
- Achieved a fast and deterministic qubit reset with 2.4% error.
- Enabled experimental concatenation over 10 times faster than passive initialization.
Conclusions:
- Feedback control offers a significant speedup for quantum experiments.
- This technique is essential for measurement-based quantum protocols like error correction and teleportation.
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