New or even revolutionary optical devices and physics are a second focus of our research. Our group was an early pioneer in negative index materials, including short-wavelength devices, as well as the use of dielectric crystals to achieve negative indices via band engineering. In addition, we have had and currently have strong programs in linear and nonlinear Si photonics. Our research in nonlinear SI photonics, for example, has led to a series of new devices and observation of new phenomena. Recently, in collaboration with IBM, we have explored high gain four-wave mixing in the mid-infrared, where two-photon-absorption is effectively zero. Finally, our group has continued to explore new optical materials and materials techniques for integrated optics including diamond, thin-film LiNbO3, and YAG. Our work with ion-slicing for example has yielded several new devices and device structures such as tunable PPLN and low-voltage modulators.
The goals of our research involve several national programs, including solar energy, data communications, biosensing, and optical interconnects. In some of these areas we have strong programs in simulation, and in others we have challenging hands-on experimentation. Our group often works closely with others within and external to Columbia.
Our work in this group uses ultrafast lasers for nonlinear optics, materials probes at Brookhaven National Lab, and advanced fabrication both at Columbia and the user Nanocenter at BNL. In addition, our group has extensive joint programs with other groups within Columbia and with out.
Figure: 1D Photonic Crystal Cavity in a Silicon waveguide
fabricated at Brookhaven National Labs.
Recent and earlier papers may be seen in our list of publications. Several examples are listed below:
R.M. Osgood, Jr., N.C. Panoiu, J.I. Dadap, X. Liu, X. Chen, I-W. Hsieh, E. Dulkeith, W.M.J. Green, and Y.A. Vlasov, “Engineering Nonlinearities in Nanoscale Optical Systems: Physics and Applications in Dispersion-Engineered Si Nanophotonic Wires,” Adv. Opt. Photon. 1, 162–235 (2009).
J.B. Driscoll, W. Astar, X. Liu, J.I. Dadap, W.M.J. Green, Y.A. Vlasov, G.M. Carter, and R.M. Osgood, Jr., “All-Optical Wavelength Conversion of 10 Gb/s RZ-OOK Data in a Silicon Nanowire via Cross-Phase-Modulation: Experiment and Theoretical Investigation,” IEEE J. Sel. Top. Quantum Electron. 16, 1448-1459 (2010).
M. Lilienblum, A. Ofan, Á. Hoffmann, O. Gaathon, L. Vanamurthy, S. Bakhru, H. Bakhru, R.M. Osgood, Jr., and E. Soergel, “Low-Voltage Nanodomain Writing in He-Implanted Lithium Niobate Crystals,” Appl. Phys. Lett. 96, 082902 (2010).
X. Liu, R.M. Osgood, Jr., Y.A. Vlasov, and W.M.J. Green, “Mid-Infrared Optical Parametric Amplifier Using Silicon Nanophotonic Waveguides,” Nat. Photonics 4, 557-560 (2010).
J. B. Driscoll, N. Ophir, R. R. Grote, J. I. Dadap, N. C. Panoiu, K. Bergman, R. M. Osgood, Jr.,”Width-modulation of Si photonic wires for quasi-phase-matching of four-wave-mixing: experimental and theoretical demonstration,” Opt. Express 20, 9227-9242 (2012).