Curriculum Vitae. Smarajit Karmakar. Educational Qualifications : Computational Skill : Personal Information : Contact Information :

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1 Curriculum Vitae Smarajit Karmakar Contact Information : Department of Chemical Physics The Weizmann Institute of Science Rehovot Israel smarajit.karmakar@weizmann.ac.il Personal Information : Permanent add : Kalikapur, Bolpur, Birbhum, West Bengal , India, Ph. No Date of Birth: January 22, Sex : Male Nationality : INDIAN Educational Qualifications : Secondary Examination ( 1996) West Bengal Board of Secondary Education Marks Obtained : 88% Higher Secondary Examination ( ) West Bengal Council of Higher Secondary Education Marks Obtained : 85% Bachelor of Science, (Physics Major) ( ) Siksha Bhavana, Visva Bharati University. Santiniketan, India. Marks Obtained : 83% Master of Science, (Physics) ( ) Centre for Condensed Matter Theory,, Indian Institute of Science. Bangalore, India MS Thesis : Liquid to Solid Transition for Hard Sphere Systems : Density Functional Theory Thesis Advisor : Prof. Chandan Dasgupta CGPA :: 7.2 (8.0) PhD ( ) Centre for Condensed Matter Theory,, Indian Institute of Science. Bangalore , India. PhD Thesis : Numerical Studies of Slow Dynamics and Glass Transition in Model Liquids Thesis Advisor : Prof. Chandan Dasgupta Computational Skill : Programming Language :: F77, F90, C, Shell Script Parallel Programming :: OpenMP, MPI System Administration :: Handling Linux Clusters

2 References Prof. Chandan Dasgupta Indian Institute of Science Bangalore , INDIA Phone: +91 (80) , cdgupta@physics.iisc.ernet.in URL: Prof. Sriram Ramaswamy Indian Institute of Science Bangalore , INDIA Phone: +91 (80) or sriram@physics.iisc.ernet.in URL: Prof. Srikanth Sastry Theoretical Sciences Unit Jawaharlal Nehru Centre for Advanced Scientific Research Jakkur Campus Bangalore , INDIA Phone: /2750 Fax: / sastry@jncasr.ac.in URL: Prof. Itamar Procaccia Department of Chemical Physics The Weizmann Institute of Science Rehovot Israel Itamar.Procaccia@weizmann.ac.il Dept. FAX: (8) Voice: (8) ( Dept. secretary) (8) (Office) URL: List of Publications : 1. Equilibrium Glassy Phase in a Polydisperse Hard-Sphere System - Pinaki Chaudhuri, Smarajit Karmakar, Chandan Dasgupta, H.R. Krishnamurthy, and A.K.Sood - Phys. Rev. Lett. 95, (2005). 2. Signatures of Dynamical Heterogeneity in the Structure of Glassy Free-energy Minima - Pinaki Chaudhuri, Smarajit Karmakar and Chandan Dasgupta, Phys. Rev. Lett. 100, (2008). 3. Growing length and time scales in glass forming liquids - Smarajit Karmakar, Chandan Dasgupta, and Srikanth Sastry, Proc. Nat. Acad. Sci. (USA) 106, 3675 (2009). 4. Size of Plastic Events in Strained Amorphous Solids at Finite Temperatures - H.G.E. Hentschel, Smarajit Karmakar, Edan Lerner, Itamar Procaccia, Phys. Rev. Lett., 104, (2010). 5. Predicting plastic flow events in athermal shear-strained amorphous solids - Smarajit Karmakar, Anael Lemaitre, Edan Lerner and Itamar Procaccia, Phys. Rev. Lett., 104, (2010). 6. Analysis of dynamic heterogeneity in a glass former from the spatial correlations of mobility - Smarajit Karmakar, Chandan Dasgupta, Srikanth Sastry, Phys. Rev. Lett. 105, (2010). 7. Comment on Scaling Analysis of Dynamic... Liquid by Stein and Andersen - Smarajit Karmakar, Chandan Dasgupta, Srikanth Sastry, Phys. Rev. Lett. 105, (2010). 8. Plasticity-Induced Anisotropy in Amorphous Solids: the Bauschinger Effect - Smarajit Karmakar, Edan Lerner, Itamar Procaccia, arxiv: (will appear in Phys. Rev. E. ).

3 9. Athermal Nonlinear Elastic Constants of Amorphous Solids - Smarajit Karmakar, Edan Lerner, and Itamar Procaccia, arxiv: ( will appear in Phys. Rev. E ). 10. Time Scales in the Theory of Elasto-Plasticity of Amorphous Solids - Laurent Boue, Peter Harrowell, Smarajit Karmakar, Edan Lerner, Itamar Procaccia, Ido Regev, Jacques Zylberg - arxiv: (submitted to Euro. Phys. Lett. ). 11. Statistical Physics of Elasto-Plastic Steady States in Amorphous Solids: Finite Temperatures and Strain Rates - Smarajit Karmakar, Edan Lerner, Itamar Procaccia, Jacques Zylberg arxiv: ( submitted to Phys. Rev. E ). 12. Finite Size Scaling Analysis of beta-relaxation regime and its connection to dynamic heterogeneity in a glass former - Smarajit Karmakar, Sumilan Banerjee, Pranabjyoti Bhuyan, Chandan Dasgupta, and Srikanth Sastry (manuscript under preparation). 13. Finite Size Scaling Analysis of Four-point Susceptibility of Glass-forming Kob-Anderson Binary Mixture - Smarajit Karmakar, Chandan Dasgupta, Srikanth Sastry (manuscript under preparation). 14. Finite Size Scaling Analysis of Kob-Anderson Binary Mixture in 2D - Shiladitya Sengupta, Smarajit Karmakar, Chandan Dasgupta, Srikanth Sastry (manuscript under preparation). Prizes: Top Rank in Bachelor of Science and Master of Science Kumari L. A. Meera Memorial Award for the year in recognition of being the best Integrated PhD Student in Physical Sciences, IISc, Bangalore, India. National Eligibility Test (NET) 2004 Recipient of Prestigious Dean's Fellowship, Weizmann Institute of Science Schools and Conferences Attended : SERC School on Statistical Physics - TIFR, Mumbai, INDIA, 16 th to 28 th February 2004 Conference and School on UNIFYING CONCEPTS IN GLASS PHYSICS III STATPHYS - 22nd Satellite Meeting School :: June 2004, Conference: 28 th June - 1 st July 2004 Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore STATPHYS22-22nd International Conference on Statistical Physics - IISc, Bangalore, INDIA July 4 th to 9 th, 2004 Advanced Graduate School in Statistical and Condensed Matter Physics - Dept. of Physics, IISc Bangalore, INDIA, January to April 2005 School on Understanding Molecular Simulations - Centre for Computational Materials Science, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore , INDIA 22 nd to 27 th January, 2007

4 Dynamical heterogeneities in glasses, colloids and granular media Lorentz Center of Leiden University, Leiden, The Netherlands August 31 th until September 6 th, 2008 School on Glass Formers and Glasses - Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India, 4 th to 20 th January, COST Strategic Workshop on "Physics of Amorphous Solids:Mechanical Properties and Plasticity" on 14 th to 19 th March 2010, in Les Houches (France). Research Experience : Density Functional Theory : liquid to crystal transition and glass transition in simple liquids we have applied density functional theory to study phase transitions in different hard sphere systems. We have studied hard sphere systems as the model liquid and the free energy of the system is calculated using the Ramkrishnan-Yussouff free energy functional. We have minimized the free energy variationally to locate the crystalline and glassy local minima. We showed that the width of the local peaks of the time-averaged density field at a glassy free-energy minimum exhibits large spatial variation, similar to that of the local Debye-Waller factor in simulations of dynamical heterogeneity. Molecular dynamics simulations starting from a particle configuration generated from the density distribution at a glassy free-energy minimum show similar spatial heterogeneity in the degree of localization, implying a direct connection between dynamical heterogeneity and the structure of glassy free energy minima. Results have been communicated in our second paper. We have also studied the freezing transition of polydisperse hard sphere systems. We have found that the freezing into a crystalline state is not possible beyond a critical polydispersity. The calculated critical polydispersity turns out to be s ~ 0.05, which is qualitatively in agreement with experimental findings. We have also found a reentrant transition in the polydisperse hard sphere system. For a given value of the polydispersity, the system first freezes into a crystalline phase as the density is increased, but if the density is increased further, crystalline phase become unstable and the system goes through another transition to a phase which we believe is glassy. This result has been already published in PRL. In this study, I have used the liquid state theory to calculate the direct correlation functions and implemented the Lubachevsky-Stillinger algorithm to generate dense random packing for hard sphere systems; these have been used as initial configurations for the free energy minimization of the glassy state. This variational minimization has been done for a very large number (~ 2500) of variables to map out the detailed density distribution of the glassy free energy minimum Finite Size Scaling for the Glass Transition We have used finite size scaling analysis, similar to that used on studies of critical phenomena near continuous phase transition, to extract a growing correlation length in glassy system. Finite size scaling is an universally accepted method in critical phenomena for extracting the underlying correlation length. Our analysis is based on the finite-size behaviour of a four-point dynamical susceptibility 4(t). We found that although the peak height of 4(t) shows normal finite-size scaling behaviour, the dependence of relaxation time on the system size is not consistent with it. We have shown that the unusual behaviour of relaxation time as function of system size can be explained using the Adam-Gibbs relation. Thus our study indicates that the energy landscape of the super cooled liquid has a strong influence on the dynamics even above the Mode Coupling temperature. The correlation length, extracted from the scaling analysis, indeed grows with decreasing temperature, but it doesn t exhibit the power law divergence at the Mode Coupling temperature predicted by the Mode Coupling theory. Our data can be better interpreted by the Random First Order Transition Theory or the Mosaic Theory, which describes the glass transition as an entropically driven transition relating configurational entropy with dynamics. We are checking the validity of different aspect of this mosaic theory by doing intensive molecular dynamics simulation for a wide range of temperature and in different dimensions. In this study, I have done intensive molecular dynamics simulation and also parallelized the code using MPI library to do some large system size simulation. In configurational entropy calculation, thermodynamic integration method has been used to calculate the bulk entropy. Inherent structures have been obtained by doing conjugate gradient minimization from which we have extracted the basin entropy by diagonalising the Hessian matrix. The difference of bulk entropy and basin entropy is

5 defined as the configurational entropy. Mechanical Properties of Amorphous Solids Linear elasticity in amorphous systems is a relatively well-understood problem, questions like how does the disorder influence the approximations to elastic constants and what are the required corrections to the Born-Huang theory have been dealt with thoroughly in the past. On the other hand, plasticity in amorphous solids is very poorly understood. In crystalline materials it is generally accepted that the microstructural objects which govern deformation and flow are a class of topological defects known as dislocations. Most work in the field of crystalline plasticity focuses on describing deformation in terms of the underlying dislocation dynamics. In the case of noncrystalline systems the situation is not so clear, even though a broad category of systems - including metallic glasses, clays and soils, pastes, foams, gels, and other so-called 'soft'' materials' -- seem to share remarkable similarities. In the past several decades much work regarding the underlying microscopic processes of amorphous plastic flow, has left many unanswered questions and much controversy. Perhaps the most important of these questions is whether or not there exist some sort of microstructural defects in the materials which, roughly speaking, play the role of the dislocations in crystals. There are some recent phenomenological theories which tried to address these questions, Shear Transformation Zone theory of Langer et al is by far the most impressive theory among them. But there also its not very clear what controls the plastic yielding. The order parameter proposed in that theory is extremely difficult to calculate if not impossible. In our recent studies on mechanical properties of amorphous solids we proposed an order parameter which can in some sense be equivalent to the order parameter proposed in the STZ theory. But a complete theory is still lacking. We also tried to find out whether one can predict the plastic failure based on the linear and non-linear elasticity at some strain value. We found out that one can in principle predict the plastic failure if one has enough information about few higher order non-linear elastic coefficients.

Length Scales Related to Alpha and Beta Relaxation in Glass Forming Liquids

Length Scales Related to Alpha and Beta Relaxation in Glass Forming Liquids Chandan Dasgupta Centre for Condensed Matter Theory Department of Physics, Indian Institute of Science With Smarajit Karmakar