Research Projects

Quantum condensed matter physics is one of the rapidly evolving research field, where the quantum mechanical theories are employed to understand the emerging properties of the materials. The interacting and collective behavior of electrons and other quasiparticles such as phonons, magnon etc. gives rise to various exotic phenomena such Superconductivity, Quantum magnetism and Topological states of matter. Topological superconductors are the materials that encompasses the nontrivial topological band structures and the superconductivity. These materials are theoretically predicted to host Majorana fermions, which are their own antiparticles. These Majorana quasi-particles obeys the non-Abelian statistics, and slated to serve as robust building blocks for fault-tolerant topological quantum computing [PRL 100, 096407 (2008), PRB 78 195125 2008, PRL 105, 077001 (2010)]. Theoretical studies have proposed the topological superconductors (TSC) to have p-wave pairing symmetry of the order parameter, which is representative of superconducting energy gap or the Cooper pair wave function. The components of order parameter reflect the directional dependence of the pairing e.g. px, py, or the chiral px+ipy (which is often referred to as p-wave due to its rotational properties). [PRL 105, 217001 (2010), PRL 107,217001 (2011)] TSC can be realized either in the intrinsic materials that have topological band structure as well as the superconductivity, or by the engineering of heterostructure of the s-wave superconductor with the topological insulator. We aims to explore the existing and new intrinsic topological superconductors PRL 100, 096407 (2008). An understanding of the complex interactions between superconductivity, magnetism, and other electronic orders in topological materials will be quite useful for fine-tuning and optimizing them for their applications in quantum computing. [arXiv:2502.12252v2] The quest for understanding unconventional superconductivity, anomalous transport, Quantum Spin liquid and the effect of quantum geometry (Berry curvature, Quantum metric) on material properties, has necessitated the emergence of new ways of studies. Thermal transport studies of materials using the Nernst coefficient and Thermal Hall effect measurement at low temperature have provided a new insight to understand the correlated quantum materials. Nernst effect and Thermal Hall effect are analogous to the classical Hall effect, where the external magnetic field applied in the perpendicular direction to the temperature gradient, gives rise to transverse charge current and thermal current, respectively. Nernst effect is a sensitive probe for studying the quasiparticle (Cooper Pairs) fluctuation and vortex dynamics in the superconductors. It is highly sensitive to the Berry curvature of bands near Fermi level in the material where electronic states are protected by the topology. The thermal Hall effect has emerged as a powerful tool for probing charge neutral excitation, spin-phonon coupling, quantum spin liquids, quasiparticle fluctuations in superconductor, and topological materials. [Phys Rev B 95, 024516 (2017)] We have already developed a set up for Nernst effect measurement as a function of temperature in the temperature range (1.8-300 K) [RSI 91, 123907 (2020)] and propose to build an experimental platform for the Thermal Conductivity and Thermal Hall Effect measurement at low temperatures. This facility will help in leapfrogging the condensed matter research in the country. Further, we’ll synthesis the good quality single crystalline topological superconductors and study them though magneto-transport, Seebeck effect, Nernst effect, thermal conductivity, and Thermal Hall effect studies.