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Statistical Physics of Plasticity in Amorphous Solids with Implications to the Glass Transition Itamar Procaccia The Weizmann Institute of Science Rehovot, 76100 Israel Work with: Smarajit Karmakar and Edan Lerner StatPhys L’viv July 4, 2012 Glass phenomenology The carriers of plasticity in crystalline materials Glasses are disordered like liquids Crystalline vs. glassy response to stress What is known about plasticity in amorphous solids? Long tradition starting with Argon, Spaepen, Langer led to the STZ theory. Basic assumptions: • There exist STZ in the material. • Plastic events include a small number of particles (30-100) • Plastic events are statistically uncorrelated So what is plasticity in amorphouas solids? Typical stress-strain and energy-strain curves in AQS systems V U 2 Statistics of Plastic Drops in the steady state 1 In the equilibrium state the probability to see zero energy barrier is zero, but NOT in the steady state Weibull’s theorem: in N random samples the minimal value observed is , In the elasto-plastic state the probability to see zero energy barrier is not zero! 1/N During a `mechanically stable’ trajectory How to find the distribution of plastic modes in the thermodynamic limit? The statistics of minimal values Weibull’s theorem: in N random samples the minimal value observed is , A very important conclusion First method: configurational entropy Second method: Finite Size Scaling Thank you!