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Relaxation and persistent oscillations of the order parameter in fermionic condensates
Emil A Yuzbashyan1, Oleksandr Tsyplyatyev, Boris L Altshuler
1Center for Materials Theory, Rutgers University, Piscataway, New Jersey 08854, USA.
Physical Review Letters
|April 12, 2006
Summary
We studied how fermionic condensates react to sudden changes. Depending on the initial state, the condensate either settles to a steady value or shows persistent oscillations.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Many-body physics
Background:
- Fermionic condensates are quantum states of matter with unique properties.
- Understanding their dynamics after perturbations is crucial for quantum technologies.
Purpose of the Study:
- To investigate the long-term behavior of a fermionic condensate after a sudden perturbation.
- To classify the different dynamic responses based on initial conditions.
Main Methods:
- Theoretical analysis of the condensate's order parameter.
- Examination of various initial states, including ground and excited states.
- Analysis of the system's approach to equilibrium or persistent non-equilibrium states.
Main Results:
- Two distinct dynamic behaviors were identified: asymptotic approach to a constant value and persistent oscillations.
- The approach to a constant value exhibits oscillatory behavior with an inverse square root decay.
- Persistent oscillations occur for specific non-equilibrium initial states, characterized by multiple frequencies.
Conclusions:
- The dynamics of a perturbed fermionic condensate are highly dependent on the initial state's classification.
- The findings provide insights into the stability and response of quantum condensates.
- This research contributes to the fundamental understanding of quantum many-body systems.
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