Colloquia & Guest Speakers

TiO2 integrated photonics: from nonlinear optics to chemical sensing

Dr. Christopher Evans

Monday, February 29, 2016
3 p.m.

Goergen Hall, Room 101


Materials innovation enables new applications. For integrated optics, new materials can enhance and even expand the scope of the existing applications. In this talk, I will present titanium dioxide (TiO2) as a promising material platform for on-chip nonlinear optical devices, quantum optics, and chemical sensing. In the first part, I will discuss my work developing TiO2 integrated optics for nonlinear optical applications. TiO2's large nonlinear index of refraction (30x of silica) and low two-photon absorption make TiO2 an excellent candidate for on-chip nonlinear optical applications. I will demonstrate the first on-chip nonlinear optics using TiO2, and discuss how we can use this platform to create a new source of entangled photons. In the second part, I will discuss my work in exploring TiO2 photonics for interrogating the surface reactivity of TiO2. To interface optics with TiO2’s surface chemistry, I design TiO2 waveguides for surface-evanescent Raman sensing. I will discuss our effort in using this spectroscopic technique to study the photochemistry on TiO2 nanophotonics and the advantages of this integrated optical approach. Lastly, I will present my perspective on how discovering and realizing new materials can expand and potentially revolutionize the field of integrated optics.


Christopher C. Evans is a Kavli Postdoctoral Fellow at Cornell University working in Jin Suntivich’s group. Chris received his Ph.D. in Applied Physics from Harvard University in 2013 working with Eric Mazur, his B.S. degree in Physics from the University of Massachusetts at Lowell in 2007, and earned a B.M. degree from Berklee College of Music in 2003. Chris was awarded a Kavli Postdoctoral Fellowship in 2014, a Harvard Quantum Optics Graduate Fellowship in 2011, a Harvard Distinction in Teaching Award in 2009, and was valedictorian of his class in 2007. During his doctoral research with Eric Mazur, Chris pioneered titanium dioxide as a novel material for integrated nonlinear optics. Inspired by the unique surface-chemical properties of TiO2, his current postdoctoral work with Jin Suntivich explores a new application of TiO2 at the interface between integrated photonics and chemistry.

Location:  Goergen 101

Refreshments will be served