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T.v. Ramakrishnan

Assistant Professor
Department of physics
BAMU University
Botswana

Biography

Area of Specialization: Theoretical Condensed Matter Physics. Professional Career: CSIR Junior Research Fellow, Banaras Hindu University, Varanasi, 1961-62. Lecturer in Physics, Indian Institute of Technology (IIT) Kanpur, Oct. 1966-March 1967. Assistant Professor, March 1967- Dec. 1967. Assistant Research Physicist, University of California, San Diego, La Jolla, California, USA, Jan. 1968 -July 1970. Assistant Professor, Indian Institute of Technology, Kanpur, Sept. 1970 - Oct.1977. Professor, IIT Kanpur, Oct. 1977- July 1980. Visiting Fellow, Princeton University, Princeton, NJ, USA, Aug. 1978- Sept.1981. Consultant, Bell Laboratories, Murray Hill, NJ, USA, July 1980-Sept.1981. Visiting Professor, Department of Physics, Indian Institute of Science, Bangalore, Oct.1981- Aug.1984. Coordinator, Research Programme on Disorder, Institute for Theoretical Physics, University of California, Santa Barbara, USA, Aug. 1983- Dec.1983. Professor, Department of Physics, Banaras Hindu University, Varanasi, Aug. 1984- April 1986. Professor, Department of Physics, Indian Institute of Science, Bangalore, April 1986-Aug. 2003. Visiting Professor and Visiting Research Physicist, Department of Physics, Princeton University, Princeton, NJ, USA, 1990-1991. Consultant, AT & T Bell Laboratories, Murray Hill, NJ, USA, 1990-1991. Honorary Professor, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore, 1993- present. INSA Srinivasa Ramanujan Research Professor, 1997-2002. Rothschild Visiting Professor, Isaac Newton Institute for Mathematical Sciences, Cambridge University, May-June, 2000. DAE Homi Bhabha Chair Professor (held in Banaras Hindu University, Varanasi, 2003-2008) Distinguished Associate, Centre for Condensed Matter Theory, Department of Physics, Indian Institute of Science, Bangalore, 2003-present. Visiting Fellow Commoner, Trinity College, and Visiting Professor, Cambridge University, 2004. Honorary Distinguished Professor, IIT Kanpur, Oct. 2004-2006. Emeritus Professor, Banaras Hindu University, Varanasi, India, 2006-present. Hindustan Lever Research Professor, 2008- present Academic Qualifications:     S. No. Degree Institution Year 1. M.Sc. Banaras Hindu University 1961 2. Ph. D. Columbia University, New York, USA 1966

Research Interest

A. PHYSICS OF ELECTRONS: Electron transport in metals, quantum many body theory. Kondo effect, local spin fluctuations, time dependent perturbations in metals. Itinerant electron magnetism, spin fluctuation effects in nearly and weakly ferromagnetic Fermi systems. Strongly correlated electron systems including mixed valent systems, heavy fermions and oxides. Electron localization, quantum interference effects in transport, weak localization. Metal-insulator and superconductor-insulator transitions. High temperature superconductivity (microscopic theory, phenomena in the mixed phase eg flux lattice melting as well as vortex dynamics and quasiparticle transport). Colossal magnetoresistance manganites. B. DISORDERED SYSTEMS: Electrons and other waves in random media. Glass transition and the glassy state. Nonequilibrium in random systems. Boson localization. C. LIQUIDS AND SOLIDS: Density wave theory of freezing, and of the solid. Relative structural stability of solids. Density functional approach to phenomena in classical condensed systems, eg. dislocations, solid solid interfaces, fracture. D. BIOLOGICAL PHYSICS: Fluctuations in cellular processes and their biological consequences; chromatin and transcription; coarse grained approaches to cellular phenomena.

Publications

  • Conductivity Scale in Disordered Systems, Phys. Rev. B28 , 6091 (1983) (with R.N. Bhatt). Density Wave Theory of Freezing and the Solid, Pramana, 22, 365 (1984). The Insulating Phase of a Disordered System : Fermi Glass vs. Electron Glass, J. Phys. C17, L639 (1984) (with R.N. Bhatt). Remarks on Large Orbital Degeneracy and on Transport Properties of Mixed Valent Systems, in Moment Formation in Solids (ed. W.J.L. Buyers, Plenum Press, New York, 1984) p. 249. Liquid to Solid Transformation, in Phase Stability and Phase Transformations, (ed. R. Krishnan, Trans. Tech. Publications, Switzerland, 1984) p. 57. Dipolar Reorientation and Phase Transition in Mixed Alkali Halide/Alkali Cyanide Crystals, Phys. Rev. Lett. 53, 2489 (1984) (with S. Nagel and J. Sethna). Theory of Anomalous Hall Effect in Kondo Lattice and Mixed Valent Systems, in Valence Fluctuations, (eds. E. Muller-Hartmann and D. Wohlleben, North Holland, 1984) p.493 (with P. Coleman and P.W. Anderson). Fluctuation Theory of Specific Heat of Liquid He 3 , Phys. Rev. B31, 2825 (1985) (with S.G. Mishra). Ultrasonic Attenuation in Strongly Disordered Electronic Systems, Phys. Rev. B31, 8188 (1985) (with G. Kotliar). Localization and Interaction Effects in Anisotropic Disordered Systems, Phys. Rev. 32, 569 (1985) (with P. Wolfle and R.N. Bhatt). Theory of Anomalous Hall Constant of Mixed Valence Systems, Phys. Rev. Lett. 55, 414 (1985) (with P.W. Anderson and P. Coleman). Metal Insulator Transition in Disordered Systems, in Recent Advances in Theoretical Physics, (R. Ramachandran, Ed., World Scientific, Singapore, 1985). p.283. Instability of the Mean Boson Field Solution for Strongly Correlated Fermi Systems, J. Phys. C19, L1 (1986). Metal-Insulator Transition in Advances in Solid State Chemistry (Ed. C.N.R. Rao, Indian National Science Academy, New Delhi, 1986) p. 217. Theory of the Mixed Valent State, J. Mag. and Mag. Materials 63 & 64 , 529 (1987). High Temperature Superconductivity in Mixed Valent Copper Oxides: Relation Between Tc and the Nominal Cu3+ Cu2+ Ratio, Solid State Comm.63, 835 (1987) (with K. Sreedhar and C.N.R. Rao). Absorption of Electromagnetic Radiation by Superconducting Y Ba2Cu3O7: An Oxygen Induced Phenomenon (with S.V. Bhat, P. Ganguly and C.N.R. Rao) J. Phys. C20 , L559-63(1987). Microscopic Theory of Strongly Correlated Fermi Systems, in Theoretical and Experimental Aspects of Valence Fluctuations and Heavy Fermions, (eds. L.C. Gupta and S.K. Mallik, Plenum, New York, 1987) p. 109 (with B.S. Shastry). Some Remarks on the Gutzwiller Wave Function, ibid., p. 509 (with B.S. Shastry). Energies of Mixed Valent Systems, ibid., p. 521 (with Leena Chandran and H.R. Krishnamurthy). Density Wave Theory of Dislocations in Solids, Phys. Rev. B37, 1936 (1988) (with M. Raj Lakshmi and H.R. Krishnamurthy). Hole Spin Model for Oxides, Physica C 153-155, 555 (1988). Conference Summary (Theory):Proceedings of the 6th International Conference on Crystal Fulde Effects and Heavy Fermion Physics (eds. W. Assmus, P. Fulde, B. L�uthi, F. Steglich), Int. J. Mag. and Mag. Materials, 76-77, 657 (1988). Disordered Superconducting Thin Films, in Physics of Low Dimensional Systems (Nobel Symposium 73, eds. S. Lundqvist and N.R. Nilsson), Physica Scripta T27, 24, (1989). Dielectric Properties of Glasses Prepared by Quenching Melts of Superconducting Bi-Ca-Sr-Cu-O Cuprates, Appl. Phys. Lett. 55, 75 (1989) (with K.B.R. Varma, G.N. Subbanna and C.N.R. Rao). Systematics in Thermopower Behaviour of Several Series of Bi and Tl Cuprate Superconductors, Physica C 165, 183 (1990) (with C.N.R. Rao and N. Kumar). Theory of Freezing (Proceedings of Seventh International Conference on Liquid and Amorphous Metals, Kyoto, Sept. 1989, North Holland, Amsterdam), J. Noncryst. Solids, 117-118, 852 (1990). Mott Transition and the Strongly Correlated Metal (International Conference on Physics of Highly Correlated Electron Systems, Santa Fe, Sept. 1989), Physica B163, 34 (1990). The Mott Transition (Invited Talk at the Raman Centenary Symposium, Dec. 1988, Bangalore) Current Science, 59, 1125 (1990). Electronic States in a Disordered Metal; Magnetic Transport in Doped Ge, Phys. Rev. B42, 3406 (1990), (with T.F. Rosenbaum, S. Pepke and R.N. Bhatt). Phonons in Solids Using Liquid State Data, Phys. Rev. B44, 9944 (1991) (with H.R. Krishnamurthy and M.C. Mahato). Anomalous Enhancement of Electron Dephasing from Magnetoresistance Data in Bi2Sr2CuO6, Phys.Rev. Lett. 67, 761 (1991) (with T.W. Jing, N.P. Ong, J.M. Tarascon and K. Remschnig). Anomalous Magnetoresistance and Hall Current in the Normal State of the Cuprate Superconductors (Proceedings of the Kanazawa International Conference on High Tc Superconductors : 1991) Physica C, 185-189, 34 (1991) (with N.P. Ong, T.W. Jing, T.R. Chien, Z.Z. Wang, J.M. Tarascon and K. Remschnig). Flux Pinning and Flux Creep in High Tc Superconductors, Physica C 183, 61 (1991) (with C. Dasgupta). Freezing of the Flux Liquid in High Tc Superconductors - A Density Functional Approach, Phys. Rev. Lett. 67, 3444 (1991) (with S. Sengupta, C. Dasgupta, H.R. Krishnamurthy and G.I. Menon). Electronic Structure of High Tc Superconductors and Related Compounds, Pramana (Letters) 38, L531, 1991 (with H.R. Krishnamurthy, S. Ramasesha, D.D. Sarma, S. Seva Nimkar and P.P. Mitra). Pressure-induced Valence Changes in Mixed-Valent Systems, J. Phys. Cond. Matt., 4, 7067 (1992) (with H.R. Krishnamurthy and L. Chandran). Density Wave Theory of Freezing and of Interfaces, in Interfaces, Structure and Properties (Ed. S. Ranganathan, C.S. Pande, B.B. Rath and D.A. Smith, Oxford and IBH, New Delhi, 1993) p.33 (with S. Sengupta). Exotic Physics in the Negative-U, Extended-Hubbard Model for Barium Bismuthates, Europhysics Letters, 21, 79, 1993 (with H.R. Krishnamurthy, A. Taraphder and Rahul Pandit). Superfluid and Insulating Phases in an Interacting Boson Model : Mean Field Theory and the RPA, Europhysics Letters 22, 257 (1993) (with H.R. Krishnamurthy, K. Seshadri and Rahul Pandit). Boson Localization, in Ordering Disorder; Prospect and Retrospect: in Condensed Matter Physics eds. V.Srivastava, A.K.Bhatnagar and D.F.Naugle (AIP Conference Proceeding 286, New York, 1994) p.38. Metal Insulator Transitions - New Phenomena, New Questions : J. Solid State Chem. 111, 4 (1994). Anomalies in Free Flux-Flow Hall Effect, Phys. Rev. Lett. 73, 1699-1702 (1994) (with S. Bhattacharya and M.J. Higgins). Density Functional Theory of the FCC-BCC Interface, Europhys. Lett. 27, 587 (1994) (with S. Sengupta and H.R.Krishnamurthy). Microscopic Theory of Vortex Dynamics, Physica C 235-240, 245 (1994) (with D.M. Gaitonde). Fluid to Solid, in Topics in Condensed Matter Physics (ed. M.P. Das, Nova Science Publishers, New York, 1994). Negative-U Extended Hubbard for Doped Barium Bismuthates, Phys.Rev.B 52, 1368 (1995). (with A. Taraphder, H.R. Krishnamurthy and Rahul Pandit) Percolation Enhanced Boson Localization in the Disordered Bosonic Hubbard Model, Phys. Rev. Lett. 75, 4075 (1995). (with K. Sheshadri, H.R. Krishnamurthy and Rahul Pandit). Structure, Electron Transport Properties and Giant Magnetoresistance of Hole Doped LaMnO3 Systems, Phys. Rev. B 53, 3348 (1996) (with R. Mahendiran, S.K. Tiwary, A.K. Raychaudhuri, R. Mahesh, N. Rangavittal and C.N.R. Rao). Freezing of a Vortex Liquid in Layered Superconductors, Phys.Rev.B 54, 16192(1996) (with G.I. Menon, C. Dasgupta and H.R. Krishnamurthy). Coherence and Localization in 2d Luttinger Liquids, Phys.Rev.Lett.77 4241 (1996) (with P.W. Anderson, S. Strong and D.G. Clark). Inertial Mass of a Vortex in Cuprate Superconductors, (Phys. Rev. B 58, 11951 (1997) (with D.M. Gaitonde). High Temperature Superconductors: Facts and Theories, in Critical Problems in Physics (eds. VL Fitch, D Marlow and R Taylor, Princeton University Press, 1997) p. 180. Colossal Magnetoresistance Oxides: Phenomena and Questions, Phil. Trans. Roy. Soc. Lond. A 356, 1-15 (1998). Magnetic Field Induced idxy Order in a dx2�y2 Superconductor, (Proceedings of SNS 97, Cape Cod, USA) J. Phys. Chem. Solids, 59, 1750 (1998). Colossal Magnetoresistance in Oxides: Some Questions, in Colossal Magnetoresistance, Charge Ordering, and Related Properties of Manganese Oxides, eds.C.N.R.Rao and B.Raveau, World Scientific, Singapore, 1998. Muon-spin Rotation Spectra in the Mixed Phase of High-Tc Superconductors: Thermal Fluctuation and Disorder Effects (with Gautam I. Menon and Chandan Dasgupta), Phys. Rev. B 60,7607-7621 (1999). Electronic Properties of the Vortex State in Cuprate Superconductors, J. Solid State Chem. 148, 85-92 (1999). Effective Actions and Phase Fluctuations in d-Wave Superconductors, Phys. Rev. B 62, 6786 (2000). (with Arun Paramekanti, Mohit Randeria,and S.S.Mandal) Localization Yesterday, Today and Tomorrow, in Fifty Years of Condensed Matter Physics, eds., R.N. Bhatt and N.P. Ong, Princeton University Press, 2001, p.9-32. Quasiparticles in the Mixed Phase of Superconducting Cuprates: A Semiclassical Green's Function Approach, J. Stat. Phys. 103, 441 (2001). (with A K Rajagopal). Small Polarons in Dense Lattice Systems, J. Low Temp. Physics 126, 1055 (2002) (with G Venketeswara Pai). Ground State Vortex Lattice Structures in d-Wave Superconductors (with S S Mandal) Phys. Rev. B 65, 184513 (2002). Raman Scattering in Charge Ordered Pr0:63Ca0:37MnO3: Anomalous Temperature Dependence of Linewidth (with Rajeev Gupta, G Venketeswara Pai, A K Sood and C N R Rao) Europhysics Letters 58, 778 (2002). Zero Temperature Insulator Metal Transition in Doped Manganites, Europhysics Letters 64, 696 (2003) (with G V Pai, S R Hassan and H R Krishnamurthy). Colossal Magnetoresistance: A New Approach. Proc. Ind. Acad. Sci. (Chemical Sciences) 115, 767 (2003) (with H R Krishnamurthy, S R Hassan and G V Pai). Theory of Manganites Exhibiting Colossal Magnetoresistance, in Physics of Manganites ed. T Chatterji, Kluwer Academic Publishers, Dordrecht, Holland Feb. 2004 (Also cond-mat 0308396) (with H R Kris:hnamurthy, S R Hassan and G V Pai). Theory of Insulator Metal Transition and Colossal Magnetoresistance in Doped Manganites, Phys. Rev. Lett. 92, 157203 (2004) (with H R Krishnamurthy, S R Hassan and G V Pai). Tracking Operator State Fluctuations in Gene Expression in Single Cells, Biophysical Journal 86, 3052 (2004) (with B Banerjee, S Balasubramanian, G V Shivashankar and G Ananthakrishna). The Origins and Implications of Long-tailed Distributions in Gene Expression, PNAS 102, 4771, 2005 ( with S Krishna, B Banerjee, and G V Shivashankar). Doping and Magnetic Field Induced Insulator-Metal Transitions in Half-Doped Manganites, Phys. Rev. Lett. 94, 24727 (2005) (with O Cepas and H R Krishnamurthy). Instabilities and Insulator-Metal Transitions in Half-Doped Manganites Induced by Magnetic Field and Doping, Phys.Rev.B 73,035218(2006) ( with O Cepas and H R Krishnamurthy) Theory of the Unusual Doping and Temperature Dependence of Photomission Spectra in Manganites, Europhysics Letters 82, 47010(2008) ( with P Sanyal, Subhro Sengupta, Nandan Pakhira, HR Krishnamurthy and DD Sarma) Fluctuations in Protein Synthesis from a Single RNA Template:Staochastic Kinetics , Phys.Rev.E 79,011916 (2009) ( with D.Chowdhury and A.Garai) Stochastic Kinetics of Ribosomes: Single Motor Kinetics and Collective Properties, Phys.Rev.E 80,0111908,2009 ( with D. Chowdhury, D. Chowdhury and A. Garai) Long Range Coulomb Interaction and Nanoscale Electronic Inhomogeneities in Correlated Oxides , Phys.Rev.B. 80,12521(2009) (with Tribikram Gupta, Vijay Shenoy and H R Krishnamurthy) Intrinsic Electron Localization in Manganites, Int.J.Mod.Phys.B 24,1664(2010) ( Special Issue on 50 Years of Anderson Localization) Phenomenological Ginzburg Landau Like Theory for Superconductivity in the Cuprates : cond-mat 1007.3287 and Phys.Rev.B.83, 024510, 2011 ( with S.Banerjee and C.Dasgupta) Novel Effects of Localization Due to Intrinsic Disorder in Manganites, Eur. J.Phys.B 81,393 (2011) ( with P.Sanyal, V Shenoy and HR Krishnamuthy) Effect of pairing fluctuations on low-energy electronic spectra in cuprate superconductors; Phys, Rev.B84 (2011) 144525(with S.Banerjee and C.Dasgupta) Optical Conductivity of Manganites, Phys.Rev.B84 (2011) 085115 (with Nandan Pakhira and H R Krishnamurthy) Ginzburg-Landau like theory of high temperature superconductivity in the cuprates: emergent d-wave order; Int. J. Modern Phys. B26 (2012) 1230005 DOI: 10.1142/S0217979212300058 . B. Review Articles: Disordered Electronic Systems, Rev. Mod. Phys. 57, 287 (1985) (with P.A. Lee). The Metal Insulator Transition, in Metallic and Non-metallic States of Matter, (Sir Nevill Mott's 80th Birthday Festschrift; eds. P.P. Edwards and C.N.R. Rao, Taylor and Francis, London, 1986) p. 16. Electron Localization, in Chance and Matter (eds. J. Souletie, J. Vannimenus and R. Stora, Elsevier Science Publishers B.V., Amsterdam, 1987) p. 215. High Temperature Superconductivity, J.Phys. Chem. 93, 4414 (1989) (with C.N.R. Rao). Metal Insulator Transitions, in Current Topics in Condensed Matter and Particle Physics, (Proceedings of 2nd BCSPIN Summer School, Kathmandu, 1991; eds. J.C. Pati, Q. Shafi and Yu Lu, World Scientific, 1993) p.537. The Metal-Nonmetal Transition: A Global Perspective, in J. Phys. Chem. 99, 5228 (1995) (with P.P. Edwards and C.N.R. Rao). Metal Insulator Transitions: Whither Theory? ( in The Metal-Non Metal Transition Revisited; A Tribute to Sir Nevill Mott, eds. P.P. Edwards and C.N.R. Rao, Taylor and Francis, London, 1995) p.293. The Exotic Barium Bismuthates: A Review. Int. J. Mod. Phys. 10, 863 (1996). (with A. Taraphder, Rahul Pandit and H.R. Krishnamurthy) Many Electrons Strongly Avoiding Each Other:Strange Goings On ( book chapter in Legacy of Albert Einstein, ed.S.Wadia, World Scientific,Singapore, 2006) Modelling Colossal Magnetoresistance Manganites , J.Phys.Cond.Mat. 19,125211,2007 Strong Electronic Correlations in Solids, Current Science, 95, 1284 ,2008 ( No.9, Nov.10,2008) Basic Questions in the Physics of Manganites , to be published,2011, Reports on Progress in Physics Anderson Localization, to be published, 2011, Scholarpedia. C. Books: Non Debye Relaxation in Condensed Matter, (World Scientific, Singapore, 1987 (ed. with M. Raj Lakshmi). Physics (a text book in four volumes for classes XI and XII; for all schools affiliated to the Central Board of Secondary Education, New Delhi, India) (coauthored with five others; editor and convenor, writing team; NCERT, New Delhi, 1988-89. Chairman, writing team, and editor, completely rewritten new edition, NCERT, New Delhi, 1995). Superconductivity Today, (An elementary introduction) (Wiley Eastern, New Delhi, 1992. Second edition, Universities Press, Hyderabad, 1999).(with C.N.R. Rao).

  • Localization and Diffusion, in Stochastic Processes : Formalism and Applications, (G.S. Agarwal and S. Dattagupta, eds., Springer-Verlag, Berlin, 1983) p. 270.

  • Mixed Valent and Kondo Systems, Configurational and Fermi Liquid Approaches, in Valence Instabilities, (P. Wachter and A.H. Boppart, eds., North Holland, Amsterdam, 1982) p. 35

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