Nano-plasmonics and Nano-photonics: Applications to Enhanced Single Photon Sources, and Mid-infrared
Speaker: Irfan Bulu, Harvard University
Series: Topical Seminars
Location: Engineering Quadrangle J323
Date/Time: Monday, October 17, 2011, 4:00 p.m. - 5:00 p.m.
Plasmonics and photonics at nano-scale offer new possibilities at improving the performance of optical devices, and creating new functionality. In the first part of my talk, I will present our recent experimental and theoretical work on plasmonic nano-cavities for enhanced room temperature single photon sources based on nitrogen-vacancy color centers in diamond. I will discuss various cavity designs from the point of practical implementation, and show that the emission rate, excitation rate, and collection efficiency from single emitters can be improved significantly in an extremely small footprint device. Furthermore, I show that our scalable, top-down nanofabrication technique maintains the crucial properties of embedded NV centers, and is therefore compatible with requirements needed for realization of quantum systems based on diamond. In the second part of the talk, I will discuss our work on mid-infrared photonics. Mid-infrared is an exciting range for on chip photonic devices with important applications in gas sensing. We recently developed record high-Q (45,000) photonic crystal cavities on a CMOS compatible platform for trace gas sensing applications. I will discuss some of the methods that we developed in order to improve the quality factors of photonic crystal cavities at mid-infrared (4.5 µm), and report the observation and origin of optical bi-stability at this wavelength range. Finally, I will discuss on the prospect of future devices ranging from all-optical signal processing to on chip frequency combs at mid-infrared.
Dr. Bulu received his Ph.D. from the department of physics at Bilkent University in Professor Ekmel Ozbay’s group, for his work on photonic crystals, surface plasmons, and metamaterials. He joined Professor Loncar’s lab at Harvard University as a postdoctoral fellow. Since joining Prof. Loncar’s lab, he demonstrated an efficient room temperature single photon source based on single nitrogen vacancy centers in diamond by using plasmonic nanocavities, developed optically reconfigurable photonic crystal filters, and worked on photonic crystal cavities at mid-infrared for sensing applications. He also collaborated with Schlumberger Limited and developed a photonic platform for oil exploration. His current research interests include non-linear diamond nano-photonic devices for quantum computing/communication applications, silicon photonics, development of new quantum emitters such as gallium nitride nanowires with embedded quantum dots/wells, and graphene plasmonics. His research resulted in more than 40 journal publications.