OVER HALF-A-DOZEN eminent scientists presented their papers on different topics on the second day of the five-day international workshop on the ‘Physics of Mesoscopic and Disordered Materials’ at the Indian Institute of Technology (IIT-K) here on Tuesday.
A senior scientist from the Tata Institute of Fundamental Research (Mumbai) Dr S Bhattacharya spoke on ‘Seeing the forest but not the trees: Imaging of condensed matter in the Meso Scale’. He said recent development in scanning probe techniques have allowed for imaging condensed matter ground states such as ferro magnets, ferroelectrics and super conductors. The scale of imaging in many of these cases was much larger than the basic unit of the building blocks, but was comparable to the correlation length of the relevant order parameter in the ground state where disorder disrupted long range spatial order.
AM Jayannavar and Mamta Sahu from the Institute of Physics, Bhubaneswar said recent developments in non-equilibrium statistical mechanics have led to the discovery of some exact and intriguing theoretical results for systems arbitrarily far away from equilibrium.
A.K.Raychaudhuri spoke about ‘Electrical noise and meso scopic fluctuations in metallic nano wires’. He said meso scopic fluctuations led to instabilities in metallic nano wires and these fluctuations in turn led to noise in electronic conduction in the nano wires. He said this excess noise and meso scopic fluctuation could be detected through sensitive noise measurements.
{{/usCountry}}A.K.Raychaudhuri spoke about ‘Electrical noise and meso scopic fluctuations in metallic nano wires’. He said meso scopic fluctuations led to instabilities in metallic nano wires and these fluctuations in turn led to noise in electronic conduction in the nano wires. He said this excess noise and meso scopic fluctuation could be detected through sensitive noise measurements.
{{/usCountry}}Vijay Singh from Homi Bhabha Centre, Mumbai spoke about the defects in semi-conductors nano structures and said impurities played a pivotal role in creating problem in semi conductors. He said one part in a million of phosphorous in silicon altered the conductivity of the super conductors by several orders of magnitude.
G.Bhaskaran from Institute of Mathematical Sciences, Chennai said following the seminal discovery of superconductivity in boron doped diamond, a mechanism of super conductivity, based on strong electron correlations could be formed. He said the theory proved that diamond acted as a template for an impurity banned phenomena and proposed that similar superconductivity should occur in a host of insulators.
D.Jaiswal Nagar and others from Tata Institute of Fundamental Research discussed the ‘Inter play between non local electro dynamics, interaction between vortices’ and said the single crystal of boro carbide superconductors were convenient test beds to study a variety of issues like the non-local effects in influencing the local symmetry at low fields.
T.Senthil from Indian Institute of Sciences, Bangalore while dwelling upon ‘Spin Fluid and Spin Nematic States of frustrated Quantum Magnets’, said despite the tremendous progress in the theoretical understanding of non-neel ground states of quantum magnets, there were as yet few unambiguous experimental examples of such states. Very recently a number of promising experiments appeared on some quantum magnets on triangular lattices.