IEEE Photonics Society Distinguished Lecture with Siddharth Ramachandran

6:30 pm on Thursday, October 10, 2013
MIT Lincoln Laboratory, 244 Wood St., Lexington, Mass.
Boston IEEE Photonics Society
IEEE Photonics Society Distinguished Lecturer

Scaling Network Capacity by Twisting Light

With Siddharth Ramachandran
Boston University

Abstract: In the last decade, perhaps the most extensively studied complex beam-shape of light is the class of vortex beams, which possess phase or polarization singularities. These beams are interesting because they resemble the emission patterns of single molecule dipoles, and they carry orbital angular momentum in addition to spin (polarization). They have several potential applications, such as laser-based electron and particle acceleration, higher-dimensional quantum encryption, information capacity scaling, single-molecule spectroscopy and nano-scale imaging.

A recently developed fiber that resembles an anti-guide, which closely mirrors the field profile of optical vortices, has enabled their stable generation and propagation in optical fibers, for distances of up to kilometres for the first time. This talk will discuss recent results and intriguing possibilities enabled by fiber propagation of beams that have long been considered interesting, but hitherto unstable in nature. Specifically, we will consider their ramifications for scaling the data-transmission capacity of optical fiber networks using orbital angular momentum as a new degree of freedom.

Recommended reading before the seminar:

Biography: Dr Siddharth Ramachandran obtained his Ph.D. in Electrical Engineering from the University of Illinois, Urbana-Champaign, in 1998. Thereafter, he joined Bell Laboratories as a Member of Technical Staff and subsequently continued with its spin-off, OFS Laboratories. After a decade in industry, Dr. Ramachandran moved back to academics in 2010, and is now a Professor in the Department of Electrical Engineering at Boston University.

Prof. Ramachandran’s research focuses on the optical physics of guided waves. He has authored over 200 refereed journal and conference publications, more than 45 invited talks, plenary lectures and tutorials, 3 book-chapters, edited one book, and has been granted 35 patents. For his contributions in the field of fiber-optics, he was named a Distinguished Member of Technical Staff at OFS Labs in 2003, and a fellow of the Optical Society of America (OSA) in 2010, and an IEEE Distinguished Lecturer for 2013-2014. He served as a topical editor for Optics Letters from 2008-2011, and is currently an associate editor for the IEEE Journal of Quantum Electronics, in addition to serving on numerous conference and grant-review committees in the field of optics and applied physics.

This meeting begins at 6:30 PM Thursday, October 10th, 2013 and will be located in the cafeteria at MIT Lincoln Laboratory, 244 Wood Street, Lexington, MA 02420. The meeting is free and open to the public. All are welcome. Prior to the seminar there will be social time and networking from 6:30 - 7:00PM in the MIT Lincoln Laboratory cafeteria, the seminar will begin at 7:00PM. For more information contact David Scherer, Boston IEEE Photonics Society Chapter chair at, or visit the Boston IEEE Photonics Society website at

Directions to Lincoln Laboratory: (from interstate I-95/Route 128)

From Exit 31B
Take Exit 31B onto Routes 4/225 towards Bedford - Stay in right lane
Use Right Turning Lane (0.3 mile from exit) to access Hartwell Ave. at 1st Traffic Light.
Follow Hartwell Ave. to Wood St. (~1.3 miles).
Turn Left on to Wood Street and Drive for 0.3 of a mile.
Turn Right into MIT Lincoln Lab at the Wood Street Gate
Have a valid driver’s license to present to security.

From Exit 30B
Take Exit 30B on to Route 2A - Stay in right lane
Turn Right on to Mass. Ave (~ 0.4 miles - opposite Minuteman Tech.).
Follow Mass. Ave for ~ 0.4 miles.
Turn Left on to Wood Street and Drive for 1.0 mile.
Turn Left into MIT Lincoln Lab at the Wood Street Gate
Have a valid driver’s license to present to security.

All attendees must present a valid driver's license to MIT Lincoln Laboratory security. To get to the Cafeteria, proceed toward the Main Entrance of Lincoln Laboratory. Before entering the building, proceed down the stairs located to the left of the Main Entrance. Turn right at the bottom of the stairs and enter the building through the Cafeteria entrance. The Cafeteria is located directly ahead.