Welcome to the Integrated Optics and Nanophotonics Laboratory!
The key words
hitting the hart of what we are doing are guided modes on
gratings, optics of nanostructured materials, and
sub-diffraction features in laser annealing and ablation.
fabricate, test, and simulate optoelectronic devices employing
waveguide gratings and nanostructured materials. We study
physics of light interaction with such objects. Practical
applications are mostly in the areas of optical communication
and optical sensors.
provide phase matching of waves with different wavevectors and
thus facilitate interactions that would be impossible or
extremely inefficient in a uniform medium. Examples include
coupling between free-space beams and guided modes, in-plane
Bragg resonances turning a waveguide grating into a 1D or 2D
photonic crystal, wavelength selection in optoelectronic devices
such as semiconductor lasers or fiber filters using Bragg
gratings, grating assisted harmonic generation and parametric
conversion in nonlinear materials, fine-tune of the quantum
selection rules in generation of entangled photons, and many
confinement and guiding in most of cases is achieved in
transparent dielectrics and relies on the total internal
reflection, the Bragg reflection in photonic crystal
waveguides, strong reflection from a metallic surface in
microwave-style pipe waveguides, or on the collective excitation
of the electromagnetic field and plasma of free electrons in
metals in case of surface plasmons.
Nanostructuring offers a tool to tailor the optical properties
of materials. Bragg gratings and photonic crystals are
considered by many as nanostructured materials as long as they
may have deep submicron features, often below 100nm. But truly
nanoscale phenomena reside at much smaller length scale. Energy
levels for electrons and holes, and thus the optical properties
of semiconductor quantum wells/wires/dots are determined,
in part, by geometry and dimensions of the structure, typically
at or below 10nm. Also, light penetration into metals is often
measured by a few dozens of nanometers only. Light interaction
with nano-scale metallic objects is a subject of nano-plasmonics.
While in a
laser annealing/ablation experiment the free-space laser beam
obeys the diffraction limit for focusing, the processed material
may reveal sub-diffraction features, in some cases approaching
the nanoscale. In a sense, light only initiates complex thermo-
and hydro-dynamic processes that shape the melted material. Tiny
holes or nano-sharp conical spikes can be manufactured at
precisely pre-determined locations on silicon-on-insulator thin
films with appropriately chosen physical parameters. These nano-structures
can also be used in optoelectronic devices.
If you are
looking for expertise in nanoscale photonics, plasmonics, guided
wave optics, or optical gratings, you are at the right place.
Take a look at our current projects, recent publications, areas
of expertise, fabrication and characterization facility. We will
be glad to work with you.