Unusual material properties induced by irradiation, doping and alloying
Abstract
The modern device concepts have triggered an interesting scientific searchfor new multifunctional materials with novel set of physical properties.One of the scientifically challenging and technologically rewardingapproaches is to explore the possibilities of inducing new novelfunctionalities by incorporating foreign elements either via energeticions or chemically, thereby harnessing the benefits of both intrinsic andextrinsic properties. Alloying, interface, imperfection and dimensionalityplay critical roles in the manipulation process leading to unexpectedcatalysis processes inside solids, magnetic properties without anymagnetic element, thermal conductivities, electronic phase separation andtransports. In this talk, I will summarize and discuss the results of anumber of studies carried out on different elemental semiconductors, wideband gap oxides and layered structure materials.
12/10/2011 at 5:30 pm
Prof. J. C. Pati, University of Maryland, USA
Special Evening Talk
Lecture Hall Block A, Institute of Physics
Document Date:
Grand Unification: A Historical Perspective and Current Status
Electronic structure, vibrational properties and spin dynamics of some selected magnetic systems
Abstract
In this presentation, I will briefly present some of the interestingstatic and dynamical aspects of few selected magnetic insulators andmetals.The electronic structure, vibrational properties and interestingdielectric nature of perovskites A(Ca,Sr,Ba)MnO3 will be discussed fromfirst principles, particularly the possibility to engineer a transitionmetal driven type-I multiferroicity in these oxides[1] will be specified.Then I will highlight some dielectric properties of Mn -doped SrTiO3 [2].In short, the quasiparticle electronic structure of thin films of localmoment systems like GdN and GdS will be reviewed [3]. Also I will presentsome of the results of the spin dynamics simulation for the magnetizationdynamics in an synthetic antiferromagnet subjected to a short pulse,particularly in terms of experimentally observed inertia like behavior init’s magnetization dynamics[4]. Finally an effort to develop a generalformalism to describe the experimentally observed spin dynamics infemto-second time scale will be discussed [5].References:[1] S. Bhattacharjee, E. Bousquet and Philippe Ghosez , Phys. Rev.Lett.,102, 117602 (2009)[2] Debraj Choudhury, P. Mandal, A. Sundaresan, Umesh V. Waghmare,Satadeep Bhattacharjee, R. Mathieu, P. Lazor, Olle Eriksson, B. Sanyal,P. Nordblad, Ajay Sharma, S. V. Bhat, O. Karis, D. D. Sarma, cond-mat.,1009.4792, (2010),[3] S. Bhattacharjee and S.M Jaya, Eur. Phys. J. B 49, 305-311 (2006) .[4] S. Bhattacharjee, A. Bergman, A. Taroni, J. Hellsvik, B. Sanyaland O. Eriksson, arXiv:1109.1414, (2011).[5] S. Bhattacharjee, L.Nordstrom and J. Fransson (in manuscript).
11/10/2011 at 11:00 am
S M Yusuf, Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai
General Seminar
Lecture Hall Block A, Institute of Physics
Document Date:
Functional Magnetic Materials: Fundamental and Technological Aspects
