Anand Sharma. Room A517, 82 University Place, Department of Physics, University of Vermont, Burlington, VT 05405, USA

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1 Anand Sharma PERSONAL DATA Date and Place of Birth : 26 th August 1979 and Bombay (Mumbai), India. Nationality : Indian Marital Status : Address : Married Room A517, 82 University Place, Department of Physics, University of Vermont, Burlington, VT 05405, USA Phone : Fax : anand.sharma@uvm.edu Webpage : RESEARCH PROFILE I have a broad interest in the physics of interacting particles in condensed matter. The principles of quantum statistical mechanics help in determining the behavior of the incredibly large number of particles interacting with each other. There exist various types of order which are illustrated in phenomenon such as magnetism or superconductivity where the collective behavior results in transitions to new phases. Using basic theoretical and numerical tools I am trying to gain an insight into the solutions to this many-body problem. PROFESSIONAL APPOINTMENTS University of Vermont, Burlington, Vermont, USA Postdoctoral Research Associate Topic: Electron- electron interaction, uniaxial strain, magnetism, van der Waals interactions and adatoms in Graphene Advisor: Prof. Valeri N. Kotov Present National Research Council of Canada, Ottawa, Ontario, Canada Postdoctoral Research Fellow Topic: Electron spin qubits in Hubbard quantum dot molecules Advisor: Prof. Pawel Hawrylak EDUCATION Humboldt University at Berlin, Berlin, Germany Ph.D. in Theoretical Condensed Matter Physics 2007 Dissertation: Electronic correlation and magnetism in multi -band Kondo lattice model: Application to real materials Supervisor: Prof. Dr. Wolfgang Nolting Indian Institute of Technology (IIT) Bombay, Mumbai, Maharashtra, India M.Sc. in Physics 2002 Thesis: Doping effects in Y 2 BaNiO 5 : a Haldane compound Supervisor: Prof. Avinash V. Mahajan K.J.Somaiya College of Science and Arts, Mumbai, Maharashtra, India B.Sc. in Physics 2000

2 FELLOWSHIPS Postdoc supported by QuantumWorks, NSERC Innovation Platform RESEARCH EXPERIENCE with Prof. Valeri N. Kotov, (Univ. of Vermont) Anisotropic Dirac fermions, electron-electron interactions and uniaxial strain in Graphene We study effects of electron-electron interaction under an applied uniaxial strain in Graphene. We calculate the electronic self-energy using perturbation theory in the long-ranged Coulomb interaction for any arbitrary value of anisotropy and consider the renormalization of dimensionless coupling constant and of electron anisotropy. We investigate the effects of applied uniaxial strain on the ferromagnetic exchange instability and formation of localized magnetic states on adatoms as well as on the spontaneous gap formation i.e., excitonic instabilities in graphene. We also study the van der Waals interaction between two strained graphene layers and the creation of polarization waves around Coulomb impurities in deformed graphene. with Prof. Pawel Hawrylak, (NRC and Univ. of Ottawa) Numerical study of quantum spin chains and quantum dot molecules Using exact diagonalization we studied the nature of low lying energy eigenvalues of quantum spins with spin, S(=1/2, 1) at each site on a one dimensional lattice and interacting with an anti-ferromagnetic Heisenberg exchange. We also analyzed the above model for a linear chain of spin 1/2 interacting with in an alternating ferro- and anti-ferromagnetic interaction. We developed the Density Matrix Renormalization Group (DMRG) algorithm for such a system. Next we considered linear arrays of triple quantum dot molecules, described with in an extended Hubbard Hamiltonian, in a field effect transistor with each molecule having an effective quantum spin, S=1. We numerically diagonalized the Hamiltonian in the parameter regime equivalent of canonically transforming it in to an effective Heisenberg-like exchange Hamiltonian. As an extension and/or application of the triple quantum dot molecules we also studied the low energy properties of a four and a six quantum dot molecule with five and nine electrons respectively as a function of inter-dot hopping and inter- dot interaction. The goal was to realize quantum dot molecule based spin qubits for quantum information processing and also maximally entangled macroscopic Greenberger- Horne- Zeilinger states in such quantum dot complexes. with Prof. Dr. Wolfgang Nolting, (HU-Berlin) Electronic correlation and magnetism in multi-band Kondo lattice model Dissertation: It concerned with a combination of many-body evaluation of a spin exchange interaction between the itinerant electrons and localized 4f moments on a periodic lattice, i.e. within the so-called multi-band Kondo lattice model (KLM), and the T=0 first principles calculations in order to study the electronic correlation effects in real materials like Europium Sulphide (EuS) and Gadolinium Nitride (GdN). The single-particle ground state energy or hopping integral acting as an input in the manybody part was obtained using tight binding linear muffin-tin orbital within atomic

3 sphere approximation (TB- LMTO- ASA) program and was a matrix in general. The electronic excitation spectrum got striking temperature dependence by its exchange coupling to the localized spin system. We also determined the pure f -spin correlations by developing the multi-band modified RKKY theory. The central idea of this theory was to average out the itinerant electron degrees of freedom from the spin - exchange interaction and map the latter on to an effective Heisenberg model. As an input for the evaluation of the effective exchange integrals, we utilize d the earlier formulated multi-band self-energy (ISA) ansatz. Using the above procedure, we determined the magnetic properties of the system like Curie temperature (within Random Phase Approximation) while calculating the chemical potential and magnetization within a self-consistent cycle. with Prof. Avinash Singh, (IIT-K) and Matthias Sperl, (Univ. Regensburg) Spin dynamics, spin-wave excitations and low temperature magnetization in diluted magnetic semiconductor (Ga,Mn)As In this study, the interplay of disorder and competing interactions was investigated in the carrier-induced ferromagnetic state of the Kondo lattice model within a numerical finite-size study in which impurity positional disorder was treated exactly. The effects of the magnon properties on finite temperature spin dynamics were quantitatively studied using a locally self-consistent magnon renormalization scheme. Competition between impurity spin couplings with increasing hole doping resulted in a strong optimization of Curie temperature highlighting the importance of compensation in diluted magnetic semiconductors. Strong cluster couplings and correlations were shown to slow down the magnetization decay and prolong magnetic ordering near Curie temperature, as also observed in magnetization measurements. We also observed an extraordinary enhancement of the spin- wave parameter compared to conventional 3d ferromagnets like Fe, which implied an enhanced low-temperature decay of the magnetic order. For a thorough understanding of this result we theoretically investigated the effect of dilution (disorder) on the finite-temperature spin dynamics and on the spin-wave parameter. We found an excellent agreement between the calculated and measured values for the spin-wave parameter. PUBLICATIONS Effect of Uniaxial Strain on Ferromagnetic Instability and Formation of Localized Magnetic States on Adatoms in Graphene A. Sharma, V. N. Kotov, and A. H. Castro Neto, Phys. Rev. B 87, (2013) Interacting Anisotropic Dirac Fermions in Strained Graphene and Related Systems A. Sharma, V. N. Kotov, and A. H. Castro Neto,, arxiv: cond-mat/ (2012) Greenberger-Horne-Zeilinger states in a quantum dot molecule A. Sharma and P. Hawrylak, Phys. Rev. B 83, (2011) Artificial Haldane gap material on a semiconductor chip Y. -P.Shim, A. Sharma, C. -Y.Hsieh, and P. Hawrylak, Solid State Comm. 150, 2065 (2010)

4 Additional carrier-mediated ferromagnetism in GdN A. Sharma and W. Nolting, Phys. Rev. B 81, (2010) Ferromagnetism in the multiband Kondo lattice model A. Sharma and W. Nolting, Phys. Rev. B 78, (2008) Spin-wave excitations and low-temperature magnetization in the dilute magnetic semiconductor (Ga,Mn)As M. Sperl, A. Singh, U. Wurstbauer, S. K. Das, A. Sharma, M. Hirmer, W. Nolting, C. H. Back, W. Wegscheider, and G. Bayreuther, Phys. Rev. B 77, (2008) Spin dynamics in the diluted ferromagnetic Kondo lattice model A. Singh, S. K. Das, A. Sharma and W. Nolting, J. Phys.:Condens. Matter 19, (2007) Temperature dependent electronic correlation effects in GdN A. Sharma and W. Nolting, J. Phys.:Condens. Matter 18, 7337 (2006) Correlation effects in the valence bands of ferromagnetic semiconductor EuS A. Sharma and W. Nolting, Phys. Status Solidi B 243, 641 (2006) Work in Progress Spontaneous gap formation in uniaxially strained graphene A. Sharma, V. N. Kotov, and A. H. Castro Neto, (2014) Polarization waves around Coulomb impurities in strained graphene V. N. Kotov, A. Sharma, and A. H. Castro Neto (2014) Van der Waals forces and electron-electron interactions in two strained graphene layers A. Sharma, P. K. Harnish, A. Sylvester, V. N. Kotov, and A. H. Castro Neto (2014) SELECTED TALKS AND PRESENTATIONS Contributed talk on 19 th March 2013 at APS March Meeting 2013, Baltimore, MD, USA on Spontaneous Gap Formation in an uniaxially strained grapheme Poster presented on 27 th June 2012 at Gordon Research Conference on Correlated Electron Systems, Mt. Holyoke College, South Hadley, MA, USA on Spontaneous gap formation in an uniaxially strained Graphene Contributed talk on 28 th February 2012 at APS March Meeting 2012, Boston, MA, USA on Formation of localized magnetic states on adatom in uniaxially strained Graphene Poster presented on 27 th July 2011 at EP2DS 19/ MSS 15, Tallahassee, FL, USA on Electron-electron interaction and anisotropic Dirac fermions in Graphene Contributed talk on 21 st March 2011 at APS March Meeting 2011, Dallas, TX, USA on Electron-electron interactions in strained Graphene

5 Contributed talk on 30 th November 2010 at Symposium I, MRS Fall Meeting 2010, Boston, MA, USA on Mechanism of ferromagnetic exchange interaction in GdN Invited talk on 14 th July 2010 at Joint Biennial NRC-McGill Meeting, Montreal, QC, Canada on Greenberger-Horne-Zeilinger states in quantum dot molecules PhD defense talk on 20 th Dec at Humboldt University at Berlin, Berlin, Germany on Temperature dependent electronic correlation effects in GdN Invited talk on 30 th March 2005 at Indian Institute of Technology Bombay, Mumbai, India on Correlation effects in the valence bands of ferromagnetic semiconductor: EuS TEACHING EXPERIENCE Humboldt University at Berlin, Berlin, Germany Teaching Assistant Winter 2005/06 Course on Classical Mechanics. Assisted Prof. W. Nolting with Spring 2006 curriculum, course assignments and grading the examination sheets. PROFESSIONAL ACTIVITIES Referee for Solid State Communications, Physica HOBBIES Reading, Traveling, Amateur photography, Theatre, Cooking. LANGUAGES Rajasthani native language (mother tongue) English speak fluently and read/write with high proficiency Hindi speak fluently and read/write with high proficiency Marathi speak fluently and read/write with high proficiency German speak, read, and write with basic competence. REFERENCES (NEXT PAGE) Prof. Valeri N. Kotov University of Vermont A522, 82 University Place, Department of Physics Burlington, VT 05401, USA valeri.kotov@uvm.edu Phone : Fax : Prof. Antonio H. Castro Neto Boston University Department of Physics

6 590 Commonwealth Ave. Boston, MA 02215, USA neto@bu.edu Phone : Fax : Prof. Pawel Hawrylak National Research Council of Canada M-50, Room No. 107, Montreal Road Ottawa, K1A 0R6, Canada pawel.hawrylak@nrc-cnrc.gc.ca Phone : Fax : Prof. Wolfgang Nolting Humboldt-Universität zu Berlin Institut für Physik, Theoretische Festkörperphysik Newtonstr. 15, D Berlin, Germany wolfgang.nolting@physik.hu-berlin.de Phone : Fax : Prof. Avinash Singh Indian Institute of Technology (IIT) Kanpur Department of Physics Kanpur , India avinas@iitk.ac.in Phone : Fax :

Anand Sharma. Institute for Theoretical Physics, J.W. Goethe- University Max-von-Laue-Str.1, D-60438, Frankfurt, Germany.

Anand Sharma. Institute for Theoretical Physics, J.W. Goethe- University Max-von-Laue-Str.1, D-60438, Frankfurt, Germany. Anand Sharma PERSONAL DATA Date and Place of Birth : 26 th August 1979 and Bombay (Mumbai), India. Nationality : Indian Marital Status : Address : Married Institute for Theoretical Physics, J.W. Goethe-