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Effective thermal dynamics following a quantum quench in a spin chain
Davide Rossini1, Alessandro Silva, Giuseppe Mussardo
1International School for Advanced Studies ,Via Beirut 2-4, I-34014 Trieste, Italy.
Physical Review Letters
|April 28, 2009
Summary
We investigated quantum Ising model dynamics after a field quench. The phase-coherence time depends on an effective temperature, mirroring equilibrium behavior.
Area of Science:
- Quantum physics
- Condensed matter physics
Background:
- The quantum Ising model describes interacting spins in a transverse field.
- Nonequilibrium dynamics are crucial for understanding quantum systems far from equilibrium.
Purpose of the Study:
- To investigate the nonequilibrium dynamics of the quantum Ising model after an abrupt transverse field quench.
- To analyze the phase-coherence time of the order parameter's autocorrelation function.
Main Methods:
- Studying the quantum Ising model with an abrupt transverse field quench.
- Analyzing the on-site autocorrelation function of the order parameter.
- Extracting phase-coherence time from asymptotic behavior.
Main Results:
- The initial state's influence on phase-coherence time is determined by an effective temperature.
- This effective temperature is set by the initial state's energy and the final Hamiltonian.
- The phase-coherence time's dependence on effective temperature matches equilibrium temperature dependence.
Conclusions:
- Effective temperature governs quantum Ising model dynamics after a quench.
- Nonequilibrium phase-coherence time behavior can be understood through an equilibrium-like temperature framework.
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