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Updated: Jul 6, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Non-markovian continuous quantum measurement of retarded observables
1Research Institute for Particle and Nuclear Physics H-1525 Budapest 114, POB 49, Hungary. diosi@rmki.kfki.hu
Physical Review Letters
|March 21, 2008
Summary
We demonstrate that non-Markovian continuous measurement of Heisenberg observables is possible using entangled von Neumann detectors. This confirms that non-Markovian quantum trajectories represent true single-system evolutions under continuous measurement.
Area of Science:
- Quantum Mechanics
- Quantum Measurement Theory
- Information Theory
Background:
- Non-Markovian quantum dynamics describe systems with memory effects.
- Continuous measurement in quantum mechanics tracks system evolution over time.
- Previous studies raised doubts about the nature of non-Markovian quantum trajectories.
Purpose of the Study:
- To investigate the realization of non-Markovian time-continuous measurement of a Heisenberg observable.
- To introduce and utilize the concept of continuous readout.
- To validate the nature of non-Markovian quantum trajectories.
Main Methods:
- Utilizing an infinite set of entangled von Neumann detectors.
- Introducing and applying the concept of continuous readout.
- Deriving the non-Markovian stochastic Schrödinger equation.
Main Results:
- Demonstrated the first realization of non-Markovian continuous measurement using entangled detectors.
- Successfully rederived the non-Markovian stochastic Schrödinger equation via continuous readout.
- Proved that non-Markovian quantum trajectories are true single-system trajectories.
Conclusions:
- Non-Markovian continuous measurement is achievable with entangled von Neumann detectors.
- Continuous readout provides a valid framework for non-Markovian quantum dynamics.
- The study resolves doubts regarding the interpretation of non-Markovian quantum trajectories.
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