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Updated: Jun 25, 2026
12:19
Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
Published on: April 4, 2017
Time-resolved measurement of a charge qubit
Georg M Reuther1, David Zueco, Peter Hänggi
1Institut für Physik, Universität Augsburg, Universitätsstrasse 1, D-86135 Augsburg, Germany.
Physical Review Letters
|March 5, 2009
Summary
We present a new method for monitoring quantum dynamics using high-frequency driving. The phase of the output signal directly measures system behavior with minimal disturbance, aiding quantum qubit control.
Area of Science:
- Quantum physics
- Quantum information science
Background:
- Monitoring quantum dynamics is crucial for controlling quantum systems.
- Existing methods often suffer from significant backaction or poor time resolution.
Purpose of the Study:
- To develop a novel, low-backaction scheme for monitoring coherent quantum dynamics.
- To enable high time-resolution measurements of quantum system evolution.
Main Methods:
- Utilizing the response of a quantum system to high-frequency AC driving.
- Employing an approximate analytical solution of the quantum master equation.
- Performing numerical simulations for a Cooper-pair box charge qubit.
Main Results:
- The phase of the outgoing signal is proportional to a specific system observable's expectation value.
- This phase can be measured experimentally using lock-in techniques.
- Coherent oscillations of a charge qubit were successfully monitored.
Conclusions:
- The proposed scheme offers a viable method for real-time monitoring of quantum dynamics.
- This technique minimizes disturbance to the quantum system, crucial for quantum computing.
- The findings are experimentally verifiable and applicable to systems like Cooper-pair boxes.
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