Department of Physics and Centre for Lasers and Photonics
INDIAN INSITUTE OF TECHNOLOGY KANPUR
RECENT RESULTS
In the press (2024)
Multi-modal sensing using plasmonic metasurface
The plasmonic metasurface made with the chosen design can sense the change in refractive index over a wide range, due to the presence of well-spaced multiple modes. More details in J. Phys. Photonics (IOP) (2024).
Optical haze in nanostructured surfaces
Both transmission haze and reflection haze from patterned surfaces can be modified by the suitable choice of pattern shape (nanodimple ND or nanobump NB), pattern size (A>B) and pattern depth (1<2). More details in Frontiers of Optoelectronics (2024).
Normal anti-reflection coatings are few-layer coatings on one side of a substrate. Our work shows that an additional single-layer coating of suitable thickness and of the right material coated on the rear-side of the substrate can improve anti-reflection further. More details in Ind. J. Phys. (2024)
Special anti-reflection coatings
One-dimensional plasmonic gratings
Plasmonic gratings of step and sinusoidal profiles are compared, and the advantages of sinusoidal profile are discussed. The grating has a specific periodicity and gold layer thickness. More details in Photonics and Nanostr. - Fundamentals and applications (2024).
Distributed Bragg reflectors do not reflect with the expected efficiency for all polarization orientations of incident light. Reflectors with line patterns replicated from CD or DVD will reflect linearly polarized light with better efficiency. More details in Thin solid films (2023).
Patterned distributed Bragg reflectors
Dual-resonant dielectric metasurface
A dielectric metasurface containing silicon nanopillars of specific size and shape will have two resonances in the near-infrared, with equally good response for anemia detection. More details in Front. Photonics (2023).
Line broadening in active fiber
Short length (1 m) of erbium-doped fiber shows homogeneous broadening while longer lengths show a certain extent of mixed line broadening nature. More details in Opt. Quant. Electr. (2023).
Tunable filter in terahertz range
By stacking two layers of perforated surfaces, it is possible to demonstrate a continuously tunable filter in the range of 100-300 GHz. More details in Opt. Quant. Electr. (2023).