Tapati Sarkar Group

The materials of interest are strongly correlated electron oxide systems. As the name suggests, these are systems where electrons interact strongly with each other, as a result of which, apart from the electronic charge, its spin and orbital also play important roles. This strong correlation gives rise to new functionalities, especially in reduced dimensions, when, in addition to the existing complexity in the systems, finite size effects also become important. Some exotic and technologically-relevant properties that have been observed in this family of materials are colossal magnetoresistance, multiferroicity, and superconductivity, to name a few.

Designing and studying such materials using new and innovative strategies is the focus of my group. We also combine experiments with theoretical modeling to understand the effect of nanostructures on the macroscopic physical properties of these materials.

Vacancy engineering in strongly correlated electron oxide systems for low-voltage resistive switches

Innovations in resistive switching devices constitute a core objective for the development of novel ultralow-power computing devices. In this work, we have demonstrated mixed charge state oxygen vacancy-engineered electroforming-free resistive switching in NiFe2O4 thin films, fabricated as asymmetric Ti/NiFe2O4/Pt heterostructures. Time-resolved measurements on the devices display both long- and short-term potentiation in the NiFe2O4 resistive switches, ideal for solid-state synapses achieved in a single system. For full details, please see here https://doi.org/10.1021/acsami.4c01501.