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Time dependence of correlation functions following a quantum quench
Pasquale Calabrese1, John Cardy
1Institute for Theoretical Physics, University of Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam, The Netherlands.
Physical Review Letters
|May 23, 2006
Summary
We reveal how quantum system dynamics can be understood using boundary critical phenomena. This approach, particularly powerful in one dimension with conformal field theory, explains quasiparticle propagation.
Area of Science:
- Quantum mechanics
- Condensed matter physics
- Statistical mechanics
Background:
- Understanding the time evolution of quantum systems is crucial in many areas of physics.
- Correlation functions provide insights into the collective behavior of quantum systems.
- Extracting dynamical information from ground states presents a significant challenge.
Purpose of the Study:
- To develop a method for extracting the time dependence of correlation functions in quantum systems.
- To connect the dynamics of extended quantum systems to boundary critical phenomena.
- To explore the applicability of conformal field theory in one-dimensional systems.
Main Methods:
- Utilizing methods from boundary critical phenomena in d+1 dimensions to analyze d-dimensional quantum systems.
- Applying conformal field theory for one-dimensional systems.
- Comparing results with those from exactly solvable models.
Main Results:
- Demonstrated that time-dependent correlation functions can be extracted using boundary critical phenomena.
- Obtained powerful results for d=1 using conformal field theory.
- Validated these findings against solvable models.
Conclusions:
- The time evolution of quantum systems can be effectively described by boundary critical phenomena.
- A general picture emerges where entangled quasiparticles propagate classically.
- Conformal field theory provides a powerful tool for one-dimensional quantum dynamics.
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