Understanding strongly-coupled systems and studying device potential of oxides

The talk will cover the highlights of recent work done at Saha Institute with my students/postdocs: 1) My group devised a strong-weak duality treatment and mapped strong- coupling problems to weak-coupling problems with the small parameter being the inverse in the dual frame of reference. We developed effective Hamilto- nians for strong electron-phonon interaction systems (with cooperative dis- tortions) and studied phase diagrams. 2) We identified minimum models for lattice supersolidity (checkerboard and diagonal striped) and clarified some important issues. 3) We proposed oxide devices as possibly the best replacement for semicon- ductor devices. Examples are: (i) High coherence charge qubit involving ox- ide double quantum dot; (ii) Giant magnetoelectric effect in pure manganite- manganite heterostructures. 4) We established correlation between battery performance and basic physics (cooperative Jahn-Teller network) in Li-battery material.