Presentations

    TiO2 as a material platform for all-optical logic, at Horizons of Nanophotonics and Nanoelectronics, Harvard University (Cambridge, MA), Monday, December 20, 2010:
    As the volume of internet traffic worldwide explodes and processing demands continually increase, solutions are required to overcome the inherent speed limitations of electronic devices. In particular, there is a need for all-optical devices, with their higher bandwidth and transmission rate, to replace various electronic functions such as routing data between processors and logic operations. We identified TiO2 as a promising yet unexplored material platform for ultrafast, on-chip nonlinear optical devices. TiO2 has a high nonlinear index of refraction (n2), enabling such operations as all-... Read more about TiO2 as a material platform for all-optical logic
    Thermally managed Z-scan measurements of titanium dioxide thin films, at Photonics West (San Francisco, CA), Thursday, January 27, 2011:
    We will present measurements of the complex nonlinear response of sputtered amorphous and polycrystalline titanium dioxide (TiO2) thin films using the thermally managed z-scan technique. Using a Ti:Sapphire laser with 100-fs pulses at 800 nm, we observe ultrafast electronic effects near TiO2's half band-gap. We explore the relation between material processing parameters and observed nonlinearity. In addition, we will discuss the consequences for applications such as all-optical switching.
    TiO2 nanophotonic waveguides for on-chip nonlinear optical devices, at Photonics West 2012 (San Francisco, CA), Monday, January 23, 2012:
    Titanium dioxide (TiO2) is a promising material for nonlinear photonic applications. Its large bandgap (> 3 eV) means it is highly transparent and has minimal two photon absorption over a wide wavelength range. TiO2’s high linear and nonlinear refractive indices (> 2 and 25 × that of silica at 800 nm, respectively) allow for high optical confinement in nanophotonic structures, such as waveguides, photonic crystals and resonators, and efficient nonlinear interactions. Thus, TiO2 is a potential platform for on-chip nonlinear optical devices operating across the three traditional... Read more about TiO2 nanophotonic waveguides for on-chip nonlinear optical devices
    Simultaneous multiphoton absorption in rutile (TiO2) across the half-bandgap, at Photonics West 2012 (San Francisco, CA), Thursday, January 26, 2012:
    Future optical systems require compact, ultra-fast devices capable of switching and logic across a wide range of wavelengths. To realize this goal, ultrafast nonlinearities must be exploited while maintaining manageable linear losses and nonlinear absorption. We present TiO2 as a nonlinear material to meet these needs. TiO2 is highly transparent for wavelengths > 400 nm and possesses both high linear and nonlinear refractive indices. We measurements the nonlinear index and multiphoton absorption in bulk TiO2 (rutile) using the z-scan technique near the half bandgap (800 nm). Using... Read more about Simultaneous multiphoton absorption in rutile (TiO2) across the half-bandgap
    Reinventing the light switch: logic with photons, at Physics Colloquium, University of Massachusetts, Lowell (Lowell, MA), Wednesday, April 25, 2012:
    Future computers and communications systems will require extremely fast logic operations that cannot be achieve efficiently using electronics. By using nonlinear optical materials with nano-scale structuring, we will show how to replace these “slow” electrons with photons to achieve logic operations on an ultrafast time scale.
    Submicrometer-width TiO2 waveguides, at CLEO (San Jose, CA), Monday, May 7, 2012:
    We fabricate submicrometer-width TiO2 strip waveguides and measure optical losses at 633, 780, and 1550 nm. Losses of 30, 13, and 4 dB/cm (respectively) demonstrate that TiO2 is suitable for visible-to-infrared on-chip microphotonic devices.