Aim of our research is to develop low-cost thermoelectric (TE) power generator for Clean Energy generation from waste heat produced at high temperatures (>800 C) in manufacturing industries, combustion engines etc. Our efforts are directed towards the discovery of new thermoelectric materials as well as device simulation and fabrication of thermoelectric generator (TEG).
In the materials development, primarily our research is focused on developing rare-earth-free, environmentally benign low-cost oxide thermoelectrics. We have developed a series of novel Double Perovskites 
) based oxides for high temperature TE applications. Although Double Perovskites (D.P.) have garnered a lot of interests from the scientific community over the years due to their various exciting properties such as magnetoresistance, multiferroicity, dielectric, multi-band Mott insulators etc. they were never been considered seriously for the thermoelectric applications. Our group has shown that D.P. can be potential candidates for high temperature TE power generation by engineering materials composition, playing with defect chemistry and manipulating processing parameters. We have shown for the first time that decoupling of phonon-glass and electron crystal behavior is possible in oxides by inducing dipolar glassy state as a result of relaxor ferroelectricity in Sr2TiCoO6 based double perovskites. We have also demonstrated metal-like electrical conductivity (~105 S/m) in Sr2TiMoO6 based ceramics, which are inherently insulator in nature. Furthermore, we have observed some very interesting behavior of colossal change in thermopower coupled with temperature driven p-n type conduction switching in D.P. oxides, hitherto, obtained only in chalcogenides. Recently we have shown for the first time that inducing octahedral ordering in a band insulator type double perovskite one can achieve reasonable electrical conductivity to get good thermoelectric power factor and figure of merit, (ZT).
Our work on double perovskites-based oxide thermoelectrics featured in Journal of Materials Research Special Focus Issue on 2019 Early Career Scholars in Materials Science published by MRS to promote outstanding research by future leaders in materials science.
Resistive Random-Access Memory (RRAM) is considered as one of the prime contenders to be the next generation non-volatile memories (NVMs). Our research in RRAM is mainly focused on unravelling the resistive switching mechanism in RRAM. Filamentary conduction paths through insulating solid electrolytes is a widely accepted theory describing the conduction phenomenon in RRAM. Using finite element modelling by COMSOL, we have proposed a novel multifilamentary conduction mechanism and developed a “3-D Multifilamentary Rupture Model” to explain multiple resistive states in transition metal oxide-based RRAM.
Furthermore, we have studied the resistance switching behavior in bilayer RRAM device structure of TiO2 with graphene oxide (GO) and reduced graphene oxide (rGO). Switching mechanism in these devices has been investigated by detailed experimental characterization in conjunction with finite element modelling simulation. We have developed a dual conical conductive filament model explaining the role of GO and r-Go in resistance switching behavior of TiO2-based bilayer heterostructure RRAM. We have demonstrated the temporal profile of electroforming process in RRAM by COMSOL FEM for the first time.
In the area of Plasmonics, our efforts have been concentrated on developing novel plasmonic lenses for the applications in optical memories, advanced photodetectors, super resolution microscopy, quantum communication etc. The challenge in this work is to control and navigate Surface plasmon polaritons (SPPs) in these plasmonic lenses in order to improve their focusing ability in the far-field without compromising their near-field intensity. We have employed 3D Finite Difference Time Domain (FDTD) simulation method in conjugation with theoretical calculation of electric field intensity and phase distribution of the emission from various plasmonic lenses in near field as well as in far-field.
We have conceptualized and designed some novel plasmonic lenses in the recent years. Our novel hybrid spiral plasmonic lenses (HSPL) inscribed with nano corrals slit (NCS) outperforms other plasmonic lenses in the near-field as well as far-field. Remarkable, we have been able to extend the focal length of hybrid plasmonic lens up to 3 
and observed a two-fold increment in the far field intensity compared to existing spiral plasmonic lens even though size of focal spot remains same. Optical complex fields produced by NCS based HSPL can be used for various applications such as super resolution microscopy, nanolithography, quantum communications, bioimaging and sensing, angular momentum detectors, etc.
Recently we have proposed a novel device scheme for designing optical memory based on 2D optical lattice of scalar vortices obtained from a novel hexagonal plasmonic lens encrypted on topological insulator like Bi2Se3, Bi1.5Sb0.5Te1.8Se1.2 etc. Analogous to Moore’s Law vis-à-vis electronic memories, Scaling of the optical information decoding devices has been proposed for the first time via increasing area density of vortices, obtained by changing radius of hexagonal lens or decreasing incident wavelength. Using these scalable optical vortex lattices, we have proposed a device scheme for storing or decoding information. Advantage of scaling in optical memories without any additional processing step shows the promise of this technology for future devices.