The seminar will take place Wednesday 28th October 2015 at 14h in the ICMCB amphitheatre.
Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, India
Summary: Starting with several very promising candidates, our search for multiferroic systems has invariably yielded negative results. Our investigations establish interesting microscopic origins of this avoidance of any long range order in such systems, particularly of the electric polarization in spite of having a large dielectric constant. In this talk, I shall discuss three very different series of compounds, namely Ln2CuTiO6 [1,2], Mn-doped SrTiO3 [3,4] and La2NiMnO6  and show that the suppression of the long range order in each case leads to some very important and interesting (magneto)dielectric properties of these materials. Additionally, we shall show that La2NiMnO6 is a true example of a multi-glassy system, while Mn-doped SrTiO3, contrary to a recent claim, is not. If time permits, I may also discuss briefly the case of Nd2NiMnO6, primarily with reference to its interesting magnetic properties .
 Debraj Choudhury et al., Appl. Phys. Lett. 96, 162903 (2010).  Debraj Choudhury et al., Phys. Rev. B 82, 134203 (2010).  Debraj Choudhury et al., Phys. Rev. B 84, 125124 (2011).  Debraj Choudhury et al., Sci. Reports 3, 1433 (2013).  Debraj Choudhury et al., Phys. Rev. Lett. 108, 127201 (2012).  Somnath Pal et al., Unpublished results.
Prof Dipankar Das Sarma studied Physics from the Indian Institute of Technology, Kanpur in 1977 and obtained a PhD from the Indian Institute of Sciences, (IISc) in Bengaluru in 1982 under the supervision of the famous Indian chemist, C.N.R. Rao. He worked as a post doctoral fellow in the Jülich Research Centre in Germany an returned to India at IISc where he obtained an assistant professorship position in 1989, and a full professor position in 1999. He is the former director of the Solid State and Structural Chemistry Unit at IISc and hold a number of academic positions in India (Kolkata, Mumbai, Pune, etc.) and abroad (Ireland, Japan, Italy, Sweeden, etc.). Prof. Sarma is a member of many professional bodies within the Department of Science and Technology in India and belongs to many Scientific Boards abroad including the Indo-French Centre for the Promotion of Advanced Science (CEFIPRA). D.D. Sarma, is very well known for his researches in the fields of Solid State Chemistry, Spectroscopy, Condensed Matter Physics, Materials Science, and Nanoscience. He published more than 400 original articles that are cited more than 11000 times.