Data and Time |
November 25 , 2010, 4:00-5:00 PM |
Location |
Sanford Flemming Building, Room B560 |
Host |
Alex Wong |
Integrated Optics: Quest for a Perfect Material
Ksenia Dolgaleva
The Edward S. Rogers Sr. Department of Electrical and Computer Engineering (Photonics)
Abstract:
The demand for high speed and high bandwidth of data transmission in
communication systems is rapidly growing. Electronic processing of optical
signals currently used in communication networks requires
optical-to-electrical and then back to optical (OEO) conversion, which
involves a lot of bulk optical components, separately fabricated, tested,
packaged, and then assembled and aligned. The role of photonic integration
at present is to replace the expensive bulk optics in transmitters and
receivers by integrated optical circuits containing all the necessary
optical components on a single chip. Practical realization of integrated
optics requires a single robust material platform for integrating multiple
optical components, including lasers, modulators, detectors, and passive
optical devices, on a single chip.
The projects that I am working on as a postdoc at the University of Toronto
are aimed at developing integrated optical devices in aluminum gallium
arsenide (AlGaAs). It is a very promising material for integrated optics
due to its mature fabrication technology, multifunctionality, and
flexibility in tailoring integrated optical devices. AlGaAs can serve as an
active medium for integrated lasers and detectors, and can also be made
passive. In addition, AlGaAs can exhibit efficient nonlinear interactions
with a negligible multiphoton absorption, which is especially important for
wavelength conversion devices that are used in wavelength division
multiplexing (WDM) communication networks. It is thus possible to
accommodate all types of integrated optical devices on a single chip based
on a single material platform.
In my talk, I will discuss wavelength conversion by cross-phase modulation
and four-wave mixing in AlGaAs with a specially designed wafer composition.
I will also talk about our recent work on integrated pulse shapers. These
devices have a broad range of applications, including communication
networks, nonlinear photonics, signal processing, optical computing,
coherent molecular excitation, and many more. My research is mostly focused
on AlGaAs material platform, but we also look into other promising
integrated technologies. I will briefly overview our work on pulse shaping
devices in femtosecond-laser-written glass Bragg gratings. Finally, I will
discuss the promise and future directions of integrated optics based on
AlGaAs that could potentially become a material platform for all-optical
communication systems of the future.
Biography:
Ksenia Dolgaleva earned her undergraduate degree in Physics from Moscow State niversity, Russia. She was awarded a prize for an outstanding
undergraduate thesis from Russian Physical Society. Ksenia has recently
completed her Ph.D. program at the Institute of Optics, University of
Rochester, USA. There she worked under the supervision of Prof. Robert Boyd
on various projects, including composite laser materials,
local-field-induced microscopic cascading in nonlinear optics, optical
activity in artificial chiral structures, cholesteric liquid crystal laser,
and single-step phase-matched third-harmonic generation in a 1D photonic
crystal. Ksenia is currently a postdoctoral fellow at the Department of
Electrical and Computer Engineering, University of Toronto, working with
Prof. Stewart Aitchison. Her current research is focused on integrated
optics in AlGaAs. Her two primary projects concern wavelength conversion by
cross-phase modulation and four-wave mixing in AlGaAs waveguides and
integrated pulse shaping devices. Ksenia co-authored 13 papers in refereed
journals, and gave 14 conference presentations. She was awarded a prize for
an outstanding student presentation at the Frontiers in Optics OSA Annual
Meeting in Rochester in October 2008.
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