Overlap Optimization of Nonlinear Frequency Conversion in Multi-Mode Cavities

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Princeton Docket # 16-3222-1

Researchers at Princeton in the Department of Electrical Engineering have invented a new computational technique for the design of a novel class of ultra-compact micro/nano-scale devices which can be used for high-efficiency nonlinear wavelength conversion in multi-mode cavities.


High-efficiency coherent wavelength conversion is crucial to various areas of science and technology such as LEDs and lasers, spectroscopy, microscopy and quantum information processing. Current technologies employ wavelength converters with bulky nonlinear crystals (e.g. LiNbO3) to convert light at readily available wavelengths to desired wavelengths. Developing ultra-compact converters with dimensions on the scale of the wavelength of light itself (sub-micron to a few microns) has been hampered by the lack of viable design techniques that can identify optimal geometries for such devices. This technique can automatically define optimal geometries that meet the stringent requirements of high-efficiency wavelength conversion in ultra-compact devices. A novel micro-post cavity with alternating material layers deployed in an unusual aperiodic sequence is used to support modes with the requisite frequencies, large lifetimes, small modal volumes, and extremely large overlaps.  This leads to orders of magnitude enhancements in second harmonic generation. An important advantage of this technology is faster operational speeds (or more operational bandwidths) over current devices for comparable or even better performance.



•       Multi-color chip LEDs

•       Lasers

•       Thin-film platforms

•       Generation of electromagnetic waves at UV and terahertz wavelength



•       Large lifetime

•       Large modal overlap

•       Faster operational speeds

•       Higher tolerance to fabrication imperfections



Zin Lin, Xiangdong Liang, Marko Loncar, Steven G. Johnson, and Alejandro W. Rodriguez. Cavity-enhanced second harmonic generation via nonlinear-overlap optimization. Optica, 3(3):233-238, 2016.



Alejandro Rodriguez is an Assistant Professor of Electrical Engineering at Princeton University. He earned his B.S. and Ph.D in Physics from MIT and was a Postdoctral Fellow at Harvard. His research is in the areas of nanophotonics, nonlinear optics, and fluctuation electromagnetic phenomena. In addition helping to develop some of the first methods for studying fluctuation interactions in complex environments, he has made significant contributions to the understanding of ways of tailoring nonlinear interaction, thermal radiation, and Casimir forces in nano-structured media. Prof. Rodriguez was the recipient of an NSF Early Career Award, the Department of Energy Fredrick Howes Award in Computational Science, and was recently named a National Academy of Sciences Kavli Fellow.


Zin Lin is a PhD candidate in Applied Physics at Harvard University John A. Paulson School of Engineering and Applied Sciences. He received his B.A. degree in Physics (with high honors) from Wesleyan University in 2012, where he worked on theoretical studies of anomalous wave transport in complex systems. He was awarded National Science Foundation graduate fellowship in 2014. His current research interests include integrated photonics, nonlinear and quantum optics, and computational design/optimization of chip-scale photonic systems.


Steven G. Johnson is a Professor of Applied Mathematics and Physics at MIT.  He works in the field of nanophotonics—electromagnetism in media structured on the wavelength scale, especially in the infrared and optical regimes—where he works on many aspects of the theory, design, and computational modeling of nanophotonic devices, both classical and quantum. He is coauthor of over 200 papers and over 25 patents, including the second edition of the textbook Photonic Crystals: Molding the Flow of Light, and was ranked among the top ten most-cited authors in the field of photonic crystals by ScienceWatch.com in 2008. In addition to traditional publications, he distributes several widely used free-software packages for scientific computation, including the MPB and Meep electromagnetic simulation tools (cited in over 1000 papers to date) and the FFTW fast Fourier transform library (for which he received the 1999 J. H. Wilkinson Prize for Numerical Software).


Marko Loncar is Tiantsai Lin Professor of Electrical Engineering at Harvard’s John A. Paulson School of Engineering and Applied Sciences. He received his Diploma (1997) from University of Belgrade (Republic of Serbia) and his and PhD (2003) from California Institute of Technology, both in electrical engineering. His recent research interests include optical nanocavities, diamond nanophotonics and quantum optics, nanoscale optomechanics, and nonlinear optics.  Dr. Loncar is recipient of NSF CAREER Award in 2009, and Alfred P. Sloan Fellowship in 2010. He is fellow of OSA and senior member of SPIE.


Intellectual Property & Development status

Patent protection is pending.

Princeton is currently seeking commercial partners for the further development and commercialization of this opportunity.



Michael R. Tyerech

Princeton University Office of Technology Licensing • (609) 258-6762• tyerech@princeton.edu

Sangeeta Bafna

Princeton University Office of Technology Licensing • (609) 258-5579• sbafna@princeton.edu



Patent Information:
For Information, Contact:
John Ritter
Princeton University
Alejandro Rodriguez
Zin Lin
Steven Johnson
Marko Loncar
Xiangdong Liang