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Quantum Zeno and anti-Zeno effects: without the rotating-wave approximation
H Zheng1, S Y Zhu, M S Zubairy
1Department of Physics, Shanghai Jiao Tong University, Shanghai 200030, China.
Physical Review Letters
|December 31, 2008
Summary
Counterrotating terms significantly impact atomic decay, extending the quantum Zeno effect (QZE) Zeno time by 2 orders of magnitude compared to previous approximations. This finding simplifies experimental QZE measurements.
Area of Science:
- Quantum physics
- Atomic decay
- Quantum Zeno effect
Background:
- Previous studies of the quantum Zeno effect (QZE) often neglected counterrotating terms.
- The rotating-wave approximation (RWA) is commonly used, potentially limiting accuracy in short-time evolution calculations.
Purpose of the Study:
- To investigate the impact of counterrotating terms on the quantum Zeno effect in atomic decay.
- To calculate electron self-energy, Lamb shift, and QZE without the RWA.
- To re-evaluate the feasibility of experimental QZE measurements.
Main Methods:
- Calculation of electron self-energy and Lamb shift.
- Quantum Zeno effect analysis without the rotating-wave approximation (RWA).
- Comparison of results with and without RWA for hydrogen in free space.
Main Results:
- Counterrotating terms have a substantial effect on short-time evolution.
- The Zeno time for hydrogen in free space is 2 orders of magnitude longer without RWA.
- Absence of an anti-Zeno effect due to counterrotating and rotating terms representing opposing high-frequency processes.
Conclusions:
- Neglected counterrotating terms are crucial for accurate QZE studies.
- The RWA significantly underestimates the Zeno time.
- Experimental measurement of the QZE may be more feasible than previously thought.
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