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Off-equilibrium effective temperature in monatomic Lennard-Jones glass
R Di Leonardo1, L Angelani, G Parisi
1Universitá di L'Aquila and INFM, I-67100, L'Aquila, Italy.
Physical Review Letters
|September 16, 2000
Summary
This study numerically investigates off-equilibrium dynamics in Lennard-Jones glasses after density jumps. The violation factor aligns with replica symmetry breaking, revealing an effective temperature related to density and glass transition temperature.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
- Computational Physics
Background:
- Understanding the off-equilibrium dynamics of glasses is crucial for materials science.
- The Lennard-Jones glass model provides a fundamental system for studying glassy behavior.
- Sudden density changes (crunches) induce non-equilibrium states relevant to glass formation.
Purpose of the Study:
- To numerically investigate the off-equilibrium dynamics of a monatomic Lennard-Jones glass.
- To study the generalized fluctuation-dissipation relation after isothermal density jumps.
- To analyze the temperature dependence of the violation factor and its relation to effective temperature.
Main Methods:
- Numerical simulations of a monatomic Lennard-Jones glass.
- Implementation of sudden isothermal density jumps (crunches).
- Analysis of the generalized fluctuation-dissipation relation and the violation factor (m).
Main Results:
- The temperature dependence of the violation factor (m) agrees with the one-step replica symmetry breaking scenario.
- At low temperatures, m(T) is proportional to T up to an effective temperature T(eff).
- The effective temperature T(eff) was reported as a function of density and compared to the equilibrium glass transition temperature T(g).
Conclusions:
- The study confirms the applicability of the replica symmetry breaking scenario to off-equilibrium glass dynamics.
- An effective temperature T(eff) characterizes the approach to equilibrium and is density-dependent.
- Comparison with equilibrium calculations provides insights into the relationship between non-equilibrium and equilibrium glass transition properties.
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