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A Method for Tracking the Time Evolution of Steady-State Evoked Potentials
Published on: May 25, 2019
Measurement of energy eigenstates by a slow detector
1Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Physical Review Letters
|May 16, 2007
Summary
We present a method for measuring quantum system energy eigenstates using a slow detector. This technique minimizes disturbance, enabling the observation of quantum jumps in harmonic oscillators.
Area of Science:
- Quantum physics
- Quantum measurement
- Quantum optics
Background:
- Continuous measurement of quantum systems is challenging due to detector backaction.
- Fast quantum systems require measurement techniques that minimize disturbance.
- Understanding quantum jumps is crucial for quantum information processing.
Purpose of the Study:
- To develop a method for weak continuous measurement of energy eigenstates in fast quantum systems.
- To limit detector backaction to decoherence of eigenstate superpositions.
- To apply this method for detecting quantum jumps in a harmonic oscillator.
Main Methods:
- Utilizing a slow detector sensitive to slowly changing variables like energy.
- Implementing a measurement scheme that minimizes backaction on the quantum system.
- Applying the developed method to a harmonic oscillator model.
Main Results:
- Demonstrated a method for weak continuous measurement of energy eigenstates.
- Showed that detector backaction can be limited to decoherence.
- Successfully applied the scheme to detect quantum jumps in a harmonic oscillator.
Conclusions:
- The proposed method allows for effective measurement of energy eigenstates in fast quantum systems.
- This technique offers a way to observe quantum jumps with minimal disturbance.
- The findings have implications for quantum control and quantum information science.
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