Name of the speaker: Prof. Rajesh V Nair
Date/time: 13th June 2025,11:00 AM
Venue: SV Narasaiah Auditorium, IAP Department
Abstract: Solid state defects like nitrogen-vacancy (NV) center in diamond or carbon defects in h-BN is a promising emitter due to its unique optical and spin properties at room temperature. The NV center emission is characterised by the feeble zero phonon line (ZPL) at 640 nm, assisted with a broad phonon-induced sideband emission. However, it is required to amplify the ZPL emission for many quantum applications involving NVs. Here, I will discuss coupling of NV centers in nanodiamonds to a metal dielectric-metal cavity at the ZPL of NV¯ (640 nm). The coupling enhances the emission rate such that the lowest achieved emission lifetime of ~6 ns with respect to a reference (~25 ns), giving Purcell enhancement ~4, in agreement with theoretical calculation. The findings are also applicable to a large variety of solid-state defects having phonon-induced decoherence. Further, I will also the attempts to generate room-temperature single photon sources and spin-selective optical transition for applications in quantum sensing.
About Speaker: Rajesh V Nair earned MSc Physics from MG University, Kerala in 2002, and PhD from IIT Bombay in 2008. After a few years of postdoctoral research in University of Twente, The Netherlands and BARC Mumbai, he started the independent research group at IIT Ropar in 2013. Currently, he is professor in Physics at IIT Ropar. He was awarded the INSA young scientist prize in physics in the year 2015, Swarnajayanti Fellowship in physical Sciences in the year 2020, and Senior Membership of OPTICA. Research Interest: Quantum Photonics and Sensing, Nanophotonics and Metamaterials.