​Abstract: Advances in computational electrodynamics have the potential to enable fundamentally new kinds of designs in nanophotonic devices which are based principally on complex, non-analytical wave-interference effects. Powerful, flexible, open-source software tools have now been made available for use in large-scale, parallel computations to model the interaction of light with practically any kind of material in any arbitrary geometry. These recent developments in computational capability make possible the investigation of various emergent structures and physical phenomena that were previously beyond the reach of pencil-and-paper analytical methods as well as less versatile and even less accessible commercial software tools. Here, I demonstrate how such advances in finite-difference time-domain (FDTD) methods for computational electromagnetism via an open-source software package known as MEEP can lead to entirely new designs for light trapping in nanostructured thin-film silicon solar cells as well as light extraction from nanostructured organic light-emitting diodes (OLEDs). In the last part of this seminar, I will provide a live demonstration of launching MEEP simulations on an on-demand high-performance computing (HPC) cluster in the cloud through our startup, Simpetus. Simpetus provides a holistic solution to the three main challenges of using simulations for research and development: 1) no software licenses or installation, 2) no hardware acquisition or maintenance and 3) technial support from the experts. The mission of Simpetus is to propel computational simulations to the forefront of photonics research and development.

Bio: Ardavan Oskooi is the Founder and CEO of Simpetus, a San Francisco- startup offering an on-demand photonics simulation platform with a mission to propel computational simulations to the forefront of photonics R&D. Ardavan received his Sc.D. from MIT where he worked with Prof. Steven Johnson and John Joannopoulos (thesis: Computation & Design for Nanophotonics) to develop MEEP (ab-initio.mit.edu/meep). Ardavan has published 13 first-author articles in peer-reviewed journals and a book "Advances in FDTD Computational Electrodynamics: Photonics and Nanotechnology” with Prof. Allen Taflove of Northwestern University and Steven Johnson. He has a masters in Computation for Design and Optimization from MIT and completed his undergraduate studies, with honors, in Engineering Science at the University of Toronto. Prior to launching Simpetus, he worked with Prof. Susumu Noda at Kyoto University and Stephen Forrest at the University of Michigan on leveraging MEEP to push the frontier of optoelectronic device design

Abstract:  The talk will describe the theory, design, fabrication, and the experimental results of an effort that led to a new type of hybrid Si/III-V semiconductor (SCL) laser with a linewidth below 1 KHz. This result is nearly 3 orders of magnitude better (smaller linewidth) than that of commercial SC lasers.

Other key parameters relevant to coherence such as the phase/amplitude coupling constant, α, and the relaxation resonance frequency are reduced by more than an order of magnitude.  The fabrication employed is CMOS compatible making the new laser integrable with electronic circuits and potentially enabling a new generation of communication, time-keeping, and sensing applications.

Bio: Amnon  Yariv  is  the  Martin  and  Eileen  Summerfield  Professor  of  Applied Physics and Electrical Engineering at Caltech. He obtained the B.S. (1954), M.S. (1956) and Ph.D. (1958) in electrical engineering from the University of California at Berkeley.   He went to the Bell Telephone Laboratories, Murray Hill, New Jersey in 1959, joining the early stages of the laser effort. He came to the California Institute of Technology in 1964. 
On the technical side, he is responsible with W.  H.Louisell and A.E. Siegman for the quantum mechanical formulation of parametric (nonlinear) optics. With students and various colleagues, he proposed and demonstrated the fields of: Optoelectronic  Integrated  Circuits  (IOECS),  the  Distributed Feedback Semiconductor laser, and coupled-resonator optical waveguide. His  recent  research  is  on  3D  lidar  imaging  with  swept  frequency semiconductor lasers and limits of coherence of semiconductor lasers. 

Dr. Yariv is a member of the American Physical Society, Phi Beta Kappa, the  American  Academy  of  Arts  and  Sciences,  the  National  Academy  of Engineering, the National Academy of Sciences, a Fellow of the Institute of Electrical and Electronics Engineers and the Optical Society of America. He was the recipient of the 1980 Quantum Electronics Award of the IEEE, the 1985 University of Pennsylvania Pender Award, the 1986 Optical Society of America Ives Medal, the 1992 Harvey Prize, the 1998 OSA Beller Medal, the National Medal of Science 2010, and the IEEE Photonics Award 2011.

Dr. Yariv was a founder and chairman-of-the-board of ORTEL Corporation (acquired  by  Lucent  Technologies in  1998),  and  is  a  founder  and  a  board member  of a  number  of  startup  companies  in  the  optical  communications field.

Abstract: The surging progress in silicon photonics over the past decade has been driven by its potential application in low cost, high bandwidth, wavelength-division multiplexed short reach optical interconnect. Despite significant advances, numerous technical challenges remain, such as the control of resonant devices, the implementation of large swing optical modulators, the management of polarization, the need for improved variation tolerance, an effective means for efficient and broadband fiber-to-chip optical coupling, and approaches to electronic-photonic integration.

In this talk, I will provide an overview of my group’s progress in addressing these issues in silicon-based photonic platforms. Photonic devices and integrated circuits implemented in standard silicon-on-insulator photonic platforms and a custom silicon nitride-on-silicon platform will be presented. I will describe microring modulators and filters that circumvent conventional limits, the first polarization rotator-splitters and controllers in standard silicon photonic platforms, grating couplers with record-setting bandwidths and insertion losses, and our ongoing efforts in electronic integration. The work paves the path toward very large- scale photonic integrated circuits and terabit-scale optical transceivers.

Bio: Joyce Poon is an Associate Professor of Electrical and Computer Engineering at University of Toronto, where she holds the Canada Research Chair in Integrated Photonic Devices. She is currently a Visiting Associate in Electrical Engineering at Caltech. She and her team conduct theoretical and experimental research in micro- and nano-scale integrated photonics

Dr. Poon obtained her Ph.D. and M.S. in Electrical Engineering from Caltech in 2007 and 2003 respectively, and the B.A.Sc. in Engineering Science (physics option) from the University of Toronto in 2002. She is the recipient of a McCharles Prize for Early Research Career Distinction, a MIT TR35 award in 2012, IBM Faculty Award in 2010 and 2011, Ontario Ministry of Research and Innovation Early Researcher Award in 2009, NSERC University Faculty Award in 2008, and the Clauser Doctoral Thesis Prize from Caltech in 2007.

Abstract: Today’s fiber-optic communication networks span the globe, delivering broadband information across all market segments and connecting massive datacenters, businesses, and individual user’s homes. As such, optical networks must operate reliably and efficiently when transporting the massive information capacity of the Internet, allowing networks to adapt to growing and changing demand flows and occasional interruptions. Wavelength-selective switches (WSS) have been instrumental in fulfilling this role, enabling all-optical spectral routing of individual wavelength-division multiplexed (WDM) communication channels at network nodes.

The recent introduction of space-division multiplexing (SDM) to the optical communication domain with new fiber types, in order to economically support the exponentially growing capacity, necessitates complementary components for implementing SDM-WDM optical networks. SDM is typically realized with either multi-core or few-mode fibers and great capacity achievements have been demonstrated to-date in each fiber solution. Wavelength-selective switching functionality for these two fiber types has recently been introduced. A joint- switching WSS concept has been realized for multi-core fibers, enabling information to be encoded and routed on the SDM-WDM optical network as a spatial super-channel (single wavelength channel spanning multiple cores). This spatial super-channel routing concept with joint-switching WSS also extends to few- mode fibers. Hence a single WSS can then be used in analogous fashion to the single-mode fiber networks, thereby heralding the cost-savings benefits of SDM. A WSS with direct few-mode fiber interfaces has been demonstrated with the few-mode beams routed in free-space just as the single mode beam does in a conventional WSS. A study on the pass band filtering effect and mode mixing due to the spectral switching of dispersed components revealed the spatial-spectral interplay in the mode-dependent loss attributes of the few- mode fiber WSS. Such advanced WSS prototypes will serve the next generation transport networks when SDM is fully adopted by carriers. 

Bio: Prof. Dan Marom joined the faculty of the Applied Physics Department in the fall of 2005, where he is pursuing his research interests in creating photonic devices for switching and manipulating optical signals. Dan earned the B.Sc. degree in Mechanical Engineering in 1989, and the M.Sc. degree in Electrical Engineering in 1995, both from Tel-Aviv University's School of Engineering. He was awarded the Ph.D. degree in Electrical Engineering by the University of California, San Diego , in 2000. From 2000 until 2005, Dan was employed as a Member of the Technical Staff at Bell Laboratories , then part of Lucent Technologies. 

Abstract: Microscopy  is  usually  performed  in  a  laboratory  on  carefully  prepared,  very  thin  samples  and  achieves resolutions  of  better  than  a  micrometer.  Medical imaging, by contrast, is usually performed on sizeable portions of the living human body, and resolutions are rarely better than 1 millimeter. Over the last decade, there has been great progress in applying optical microscopy techniques to the human body in a medical setting.  This push has been led by optical coherence tomography (OCT), which is now in mainstream use in ophthalmology and is gaining acceptance in cardiology. In this talk, 3D microscopic imaging deep inside tissue using the OCT microscope in a needle will be described. Needle delivery makes optical imaging possible in many tissues previously inaccessible to optics. Aimed  to  be broadly  accessible,  this talk  will describe the underpinning  photonics  and  guided-wave  optics design  and  fabrication  needed  to  make  high-quality  micro-imaging  possible.  Technical advances  such  as realization  of  ultra-small  needle  probes,  extended  imaging  depth  of  focus,  handheld  micrometer-resolution tracking,  and  multimodality  needle probes  combining  OCT with  fluorescence,  and  with  elastography will  be presented. It will describe how such probes are built into photonic systems and where they are being applied, such as in breast cancer surgery, as well as how the technology may evolve and where it may be applied in the future.    

Bio: Winthrop Professor Sampson is Director of the Centre for Microscopy, Characterization & Analysis, a core facility of the University of Western Australia, and heads the Optical + Biomedical Engineering Laboratory (OBEL) in the School of Electrical, Electronic & Computer Engineering. He directs the Western Australian nodes of the Australian Microscopy & Microanalysis Research Facility and Australia’s National Imaging Facility. He is a Fellow of the OSA and the SPIE, and an Associate Editor of IEEE Photonics Journal, the IEEE Transactions of Biomedical Engineering and on the editorial boards of the Journal of Biomedical Optics and the journals Photonic Sensors and Photonics & Lasers in Medicine. W/Prof. Sampson’s research interests are in biomedical optical engineering, with an emphasis on photonics, imaging and microscopy. His current main interest, beyond advancing microscope-in-a-needle technology, is in optical elastography – the imaging of tissue mechanical properties. His other interests include anatomical optical coherence tomography for imaging in human airways, and holographic microscopy.