Fri, Jan 28, 2011 @ 10:00 AM - 11:00 AM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Avi Zadok, Bar-Ilan University
Talk Title: Polarization Attributes of Stimulated Brillouin Scattering in Fibers
Abstract: Stimulated Brillouin scattering (SBS) is a nonlinear optical interaction between a pump wave, and a typically weaker, counter-propagating signal wave. The threshold power of SBS is the lowest of all nonlinear propagation effect in silica optical fibers. The local SBS interaction, at a given point along an optical fiber, is maximal when the state of polarization (SOP) of the pump is aligned with that of the signal, and it vanishes if the two SOPs are orthogonal. In standard single mode fibers, the overall SBS signal amplification (or attenuation) depends on the birefringence properties of the fiber, as well as on the input SOPs of both the pump and the seed signal waves. As SBS is studied intensively for applications such as fiber lasers, distributed sensing and slow light, a thorough examination of its polarization properties is of large relevance.
In this talk, the SBS amplification of an arbitrarily polarized input signal in a randomly birefringent fiber is examined, as well as the role of SBS in the evolution of the signal SOP. The analysis includes Stokes and anti-Stokes waves. A propagation equation for the signal SOP is formulated and analyzed, in Jones and Stokes spaces. In particular, it is found that the output SOP of an SBS amplified Stokes wave in a standard, single mode fiber is drawn towards the complex conjugate of the input pump SOP. On the other hand, the output SOP of the residual, attenuated anti-Stokes signal is repelled from the same SOP. These findings are supported by simulations and experiments. The results are applicable to random SOP synthesis, coherent detection of fiber sensors, advanced modulation formats and implementations of optical filters. Finally, the role of polarization in SBS-based \'slow light\' setups is addressed.
Biography: Avi Zadok received his Ph.D. in Electrical Engineering from Tel-Aviv University in 2007. In between 2007-2009 he was a post-doc fellow with the group of Prof. Amnon Yariv at the Department of Applied Physics, California Institute of Technology. In 2009 he was appointed as a senior lecturer at the School of Engineering, Bar-Ilan University. His research interests include silicon-photonic devices, fiber-optic communication and sensors, microwave photonics and nonlinear optics.
Host: Prof. Alan Willner, email@example.com
Audiences: Everyone Is Invited
Contact: Gerrielyn Ramos