Room: B430 Engineering Quadrangle
My specialty is theoretical condensed matter (solid-state) physics. My research has encompassed a wide variety of subfields, concentrating on disordered and/or strongly interacting (correlated) electronic materials in the past two decades. More recently, our emphasis has been in two areas – (i) magnetism and transport in in disordered electronic systems such as doped and diluted magnetic semiconductors, and (ii) two-dimensional electron systems (e.g. semiconductor heterostructures and graphene) in a strong magnetic field (the quantum Hall regime). Our research combines analytical methods, such as the concept of scaling, with numerical methods, such as Monte Carlo simulations, transfer matrix approach, and other matrix techniques to study fundamental properties of electronic materials . Recently, for example, we have studied (1) the nature of the magnetism in diluted magnetic semiconductors; (2) ground states of dopant clusters in quantum dots; and (3) properties of electronic eigenstates in disordered nanowires, to name a few. Calculations are carried out on high-performance multiprocessor computer arrays. Much of our research is motivated by, and closely related to, experimental systems. Currently we’re focusing our efforts on uncovering the design principles for fractional quantum Hall states, to determine the feasibility of topological quantum computing.
Importance of Rare Fluctuations in Quantum Condensed Matter Systems, Invited Colloquium at the Indian Condensed Matter Program 2009, organized by Indian Center for Theoretical Sciences, Mahabaleshwar, India, December 2009.
Ferromagnetism in a disordered Hubbard model, Invited talk at ICMW08 - Indian Condensed Matter Workshop organized by Tata Institute of Fundamental Research at Mahabaleshwar, India, December 2008.
Ferromagnetism in doped semiconductors without magnetic ions: squeezing water out of a rock, Invited talk at the Institute for Complex Adaptive Matter Workshop on Conductor-Insulator Quantum Phase Transitions, Ohio State University, Columbus, OH, January 2008.
Ferromagnetism in doped semiconductors without magnetic ions, Invited talk at the 31st International Workshop on Condensed Matter Theories (CMT31), Chulalongkorn University, Bangkok, Thailand, December 2007.
Ferromagnetism in disordered, low carrier density systems without magnetic ions, Invited talk at the Sino-German Workshop on Novel Concepts in Disordered and Interacting Quantum Systems, Hangzhou, China, March 2007.
Ferromagnetism in non-magnetic doped semiconductors, Invited talk at the Aspen Winter Workshop on “Spins in Nanostructures”, Aspen, CO, January 2007.
Ferromagnetism in Low Carrier Density Systems, Plenary talk at the Workshop on Frontiers of Condensed Matter Theory, William T. Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, MN, May 2006.
Ferromagnetism versus antiferromagnetism in low carrier density many body systems (13th International Conference on Recent Progress in Many-Body Theories, QMBT13, Buenos Aires, Argentina, December 2005 – unable to deliver due to family emergency).
Study of integer and fractional quantum Hall transitions using topological quantum numbers (XXIX International Workshop on Condensed Matter Theories, International Institute for Advanced Studies, Kizu, Kyoto, Japan, September 2005).
Disorder and Frustration effects in Diluted Magnetic Semiconductors (International Conference on Disorder, Complexity and Biology, Varanasi, India, July 2004).
Disorder and Frustration in Diluted Magnetic Semiconductors at low carrier densities (International Conference on Superconducting and Related Materials, Chongqing, China, June 2004).
Exchange frequencies and magnetic ground state of a Wigner Crystal in anisotropic two-dimensional electron systems (Conference on Ring Exchange in Condensed Matter, Cargese, France, April 2004).
Ferromagnetism in Diluted Magnetic Semiconductors (National Conference on Materials and Applications, Kurukshetra University, India, March 2004)
Effects of Clustering and Dimensionality on the Magnetic Properties of Diluted Magnetic Semiconductors (MRS Fall Meeting, Boston, December 2003)
Numerical Studies of Inhomogeneous Ferromagnetism in Diluted Magnetic Semiconductors, Third Brazilian Meeting on Simulational Physics, (Ouro Preto, Brazil, August 2003.