VIVEK NAGENDRA BHAT
Topic: Broadband Near-field Optical Spectroscopy
Date & Time: January 20, 2022 at 4.00 p.m. through MICROSOFT TEAMS
Microsoft Teams Link:
The spatial resolution in optical microscopy is limited by the diffraction-limited spot. Several super-resolution microscopy methods exist. However, most are not amenable to use with broadband femto second lasers. I will discuss a recent variant of Scanning Near-field Optical Microscopy (SNOM) which makes it possible to achieve spatial resolution beyond the diffraction limit, easily couples to broadband light, and makes signal detection against a large background feasible. This new approach relies on an “in-line interferometer” which provides better signal-to-noise and stability compared to existing SNOM approaches. I will present the experimental aspects in detail and briefly mention a recent application of this approach to characterize the local density of states in Sb2S3nanodots.
 Paul Bazylewski, Sabastine Ezugwu, Giovanni Fanchini, Appl. Sci. 2017, vol. 7, 973.
 Lukas Novotny and Stephan J. Stranick, Annu. Rev. Phys. Chem. 2006,vol. 57, 303.
 Jens Brauer, Jinxin Zhan, Abbas Chimeh, Anke Korte, Christoph Lienau, Petra Gross, Optics Express 2017, vol. 25, 15505.
 Jinxin Zhan, Wei Wang, Jens Brauer, Lukas Schmidt-Mende, Christoph Lienau, Petra Gross, Advanced Photonics, 2020, vol. 2, 046004.