What is our business?
The low temperature laboratory primarily addresses the question: "what is the true ground state of material?"
We measure the electrical and magnetic properties of the solids at temperatures as low as 2 K regularly, occasionally upto 0.3K, will very soon upto 50 mK. These studies tell us whether the system is metallic, the nature of carriers and associated magnetic state. We also measure electrical and magnetic properties of the material by applying magnetic field and discover if the magnetic field has changed the ground state of the material.
Another study that occupies us is -- how the application of pressure influences the electrical and magnetic properties of the system, if we get favourable properties; we can synthesise new materials with the desired property by application of chemical pressure, by adding suitable substituents..
It is well known that most solids show condensation into macroscopic quantum states; viz. the superconducting state, charge density wave and spin density wave states. From the fundamental understanding point of view, it is puzzle as to why certain materials prefer such exotic ground states in the first place. It is a fond hope that an understanding of all this; can help us design new materials whose property we can tinker at our will.
Our interest in superconducting materials stems from the immense possibilities of its applications. In fact the search for high transition temperature superconductors is the holy grail of condensed matter physicists world over.
The zero resistance property and the Meissner effect property of the superconductors, has immense applications in energy conservation and rapid transport systems, see link below for more details.
http://www.superconductors.org/
To be cost effective all these application require operation close to room temperature, therefore the need for materials with superconducting transition temperatures close to room temperature. Thus condensed matter physics community are in the quest of high Tc superconductivity.
The discovery of a series of cuprate superconductors in the late 1980's and subsequent practical application made possible by using the cheaper liquid nitrogen has further kindled the hope in the applications of high temperature superconductors.
Click for a video on Magnetic Levitation of Superconductors: Magnetic Levitation
We also work on SCES.. What are SCES--( strongly correlated electron systems) and why are they of immense interest
The discovery of high temperature superconductivity in the cuprates is the origin of a paradigm shift in the condensed matter research. Band structure calculations that was the back bone of conventional condensed matter physics is not valid in these systems-and they are termed as strongly correlated electron systems.
The electron-electron interaction that is taken to be a function of local electron density to understand electronic structure of Si for example, is no more valid in systems in which strong electron correlations are important. The origin of the high superconducting transition temperature, the unusual normal state properties of the cuprate superconductors are still a puzzle and is an active area of research.
In all transition metal oxides the electronic structure relevant is that of the local transition metal-O cluster, therefore tuning it to obtain the property of interest can be easy. The manganese oxides have large magneto-resistance close to room temperature and fine tuning to make it useful is a vast area of research.
Recently multi-ferroics, a property mainly found in transition metal oxides have become a topic of great interest, as in these materials an electrical property can be tuned by applying a magnetic field and magnetic property by electric field.
Added to this rich variety of physical properties, is the added possibility of tuning properties by reducing dimensions; casting these materials as thin films, and making them into nano particles adds more variety and adventure to the study of material science
Thus the wonderful world of materials is a rich play ground to let your imagination lose and who knows.. you could discover or invent new materials that could be of great use to mankind.. and change our lifestyle for the better...