Research interests of our lab includes：(I) Plasmonics, (II) Structured Light, (III) Nonlinear optics, and (IV) Ultrafast Optics.
Surface plasmon is a wave generated when light couples to electrons that are bound to the surface of a metal. This results in intense fields that decay away from the interface of the metal and the surrounding dielectric. These surface plasmons exhibit various interesting properties such as enhancement in the local fields, high sensitivity to any variation in the surrounding conditions, such as a change in dielectric parameters of the materials and the nature of the exciting light source. Due to these properties, plasmons have applications in broad fields of science. These applications include chemical and biological sensing, plasmonic solar cells, high-resolution spectroscopy and cancer treatment to name a few. Recent research in this area of a broad photonics overview demonstrates that with sub-wavelength structures many new functionalities far below the diffraction limit can be explored. This has the potential to scale down many conventional electronic and optical devices. And the beauty in all this is that it is firmly grounded in multidisciplinary fields and people with all sorts of backgrounds such as from, physics, electrical engineering, chemistry, and biosciences come together to achieve common goals.
In our group at UPL, we focus on many aspects of plasmonics. This includes the study of nanostructured meta-surfaces, plasmonic transmission lines, optical beam steering, particle trapping, light-matter interactions, non-linear optics, and ultrafast plasmonics. The potential of plasmonics can be leveraged for the development of better performing switches, modulators, sensors, and integrated optical components. We aim to explore these possibilities for practical applications. We also aim to study non-linear behavior in plasmonic nanodevices. Second and third harmonic generation can undergo significant enhancement with plasmonic nanostructures. Since metals can show high non-linear responses, they can be structured to achieve nonlinear functionalities. The nonlinear mechanisms can quite complex and thus the potential need to be extensively explored for next-generation photonic devices. Our capabilities in plasmonics include numerical calculations, device fabrication, full-vectorial optical arbitrary waveforms generations and optical measurements in both near and far fields.
Current projects in our lab related to plasmonics are:
1. Plasmonic beam steering and routing.
In this project, we aim to achieve directional routing of SPPs using structured metasurfaces. Field control by changing properties of incoming light such as wavelength, polarization, and the incidence angle is desirable for next-generation optical circuits. We are also working on the use of genetic algorithms to achieve this task.
2. Non-linear plasmonics.
In this project, we are exploring transmission lines for second-harmonic plasmonic generations. This provides a new degree of freedom for on-chip SHG in a nanophotonics circuit and can be used for non-linear frequency conversion at nanoscales.
3. Plasmonic chemical sensing and biosensing.
In this project, we are trying to use structured metasurfaces for the sensing of complex molecules such as organic analytes and biological samples.
II. Structured Light
III. Nonlinear Optics
IV. Ultrafast Optics