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Ngai Fest September 16, 2006. Fast and Slow Dynamics in the Free Energy Landscape. T. Odagaki and T. Ekimoto Department of Physics, Kyushu University. High T. High T. Low T. Free energy. Low T. Free energy. Phase transition. Order parameter. Configuration.
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Ngai Fest September 16, 2006 Fast and Slow Dynamics in the Free Energy Landscape T. Odagaki and T. Ekimoto Department of Physics, Kyushu University
High T High T Low T Free energy Low T Free energy Phase transition Order parameter Configuration Phase Transition Glass transition : Diverging mean waiting time Free Energy Landscape
Dynamics Single particle:Gaussian to non-Gaussian transition Slow and fast relaxations Thermodynamics Specific heat: Annealed to quenched transition Cooling-rate dependence Construction of free energy landscape Dynamics Thermodynamics Phenomenology Slow and fast relaxations Fundamental Theory
Separation of time scales Total Microscopic Relaxation
Separation of time scales for where For practical calculation : Random force Free energy landscape Dynamics on the FEL [Ansatz]
A toy model for the dynamics on the FEL Dynamics Scaled equation random force and
Three models for g(T) movie
The dynamical structure factor of Model 1 ωS(k,ω) k=0.5 Jump motion 1000T0 100T0 10T0 1T0 0.1T0 Oscillatory motion 0.01T0 ω
The dynamical structure factor of Model 2 ωS(k,ω) k=0.5 Jump motion 1000T0 10T0 0.3T0 0.1T0 0.01T0 Oscillatory motion ω
The dynamical structure factor of Model 3 ωS(k,ω) k=0.5 Jump motion 100T0 10T0 1T0 0.3T0 0.1T0 Oscillatory motion 0.01T0 ω
Unified Theory for Glass Transition Single particle:Gaussian to non-Gaussian transition Slow and fast relaxations Specific heat: Annealed to quenched transition Cooling-rate dependence Construction of free energy landscape Dynamics Thermodynamics Phenomenology Dynamics Thermodynamics Fundamental Theory
: Direct correlation function Ramakrishnan-Yussouff free energy functional Free energy landscape as a function of
No of atoms in the core :32 String motion and CRR
Simultaneously and cooperatively rearranging regions SRR: Difference between two adjacent basins CRR: Atoms involved in the transition state return
Energy of basin a Probability of being in basin a at t a :Quenched :Annealed Phenomenological understanding : Heat capacity T. Tao &T.O(PRE 2002),T.O et al (JCP 2002),T. Tao et al (JCP2005)
slow fast T. Tao, T. O and A. Yoshimori: JCP 122, 044505 (2005) • 20 basins:Einstein oscillators Annealed-to-quenched transition and cooling rate dependence return
Waiting time distribution for jump motion Trapping Diffusion Model return
Characteristic Temperature Equation Unifying concept
Characteristic Temperature Equation V B Kokshenev & P D Borges, JCP 122, 114510 (2005) return
:Size of CRR by Adam and Gibbs CRR Prob. of activation free energy Waiting time distribution SRR Waiting time distribution for slow relaxation return
Non-Gaussian parameter Susceptibility return