In this thought-provoking episode, Dr. Ghimire joins us to discuss his research on topological nanospasers, an emerging field of study with vast potential for applications in diverse areas including infrared spectroscopy, sensing, probing, and biomedical treatment.

A topological nanospaser, as Dr. Ghimire explains, is a system consisting of a silver nanospheroid and a MoS2 monolayer flake with a circular shape. The metal nanospheroid functions as a plasmonic nanoresonator, supporting two rotating modes, which are coupled to the corresponding valleys of MoS2. When external circularly polarized light is applied, it selectively pumps only one of the valleys of MoS2, and this interaction underpins the generation of the spaser dynamics.

Dr. Ghimire elaborates on how the generated spaser dynamics are strongly influenced by the size (radius) of the MoS2 nanoflake. For a small radius, the system has a single spasing regime where only the chirally matched plasmon mode is generated. However, as the size of the MoS2 increases, there can be two distinct regimes depending on the pump intensity. In one regime, only the chirally matched plasmon mode is generated, while in the other, both chirally matched and chirally mismatched modes can exist. Fascinatingly, these different spaser operation regimes have opposite handedness in the far-field radiated spaser system.

This episode provides a deep dive into the exciting world of topological nanospasers. Whether you're a physicist, a researcher, a student or simply interested in the latest breakthroughs in nanotechnology, this conversation with Dr. Ghimire is sure to captivate you.

Keywords: Topological nanospaser, Silver nanospheroid, MoS2 monolayer flake, Plasmonic nanoresonator, Rotating modes, Valleys, External circularly polarized light, Spaser dynamics, Chirally matched plasmon mode, Chirally mismatched mode, Infrared spectroscopy, Sensing, Probing, Biomedical treatment.

https://doi.org/10.1021/acsphotonics.0c01919