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    Less is More: Extreme Optics with Zero Refractive Index, at Photonics West 2016, Integrated Optics: Devices, Materials, and Technologies XX (San Francisco, CA), Monday, February 15, 2016:
    talk_2569.pdf
    Nanotechnology has enabled the development of nanostructured composite materials (metamaterials) with exotic optical properties not found in nature. In the most extreme case, we can create materials which support light waves that propagate with infinite phase velocity, corresponding to a refractive index of zero. This zero index can only be achieved by simultaneously controlling the electric and magnetic resonances of the nanostructure. We present an in-plane metamaterial design consisting of silicon pillar arrays, embedded within a polymer matrix and sandwiched between gold layers. Using an... Read more about Less is More: Extreme Optics with Zero Refractive Index
    Nonequilibrium materials: using ultrafast laser pulses to change band structures, at SPIE Conference on Ultrafast Bandgap Photonics (Baltimore, MD), Sunday, April 17, 2016:
    talk_2540.pdf
    Soon after it was discovered that intense laser pulses of nanosecond duration from a ruby laser could anneal the lattice of silicon, it was established that this so-called pulsed laser annealing is a thermal process. The past two decades have show that ultrashort laser pulses in the femtosecond regime can induce athermal, nonequilibrium processes that lead to either transient phase changes in semiconductors through ultrafast ionization or permanent phase changes through nonequilibrium doping. In this talk we will review work in both of these regimes and show how ultrafast lasers can be used... Read more about Nonequilibrium materials: using ultrafast laser pulses to change band structures
    Non-equilibrium materials by fs-laser texturing and hyperdoping of silicon, at AFOSR Ultrashort Pulse Laser-Matter Interactions PI Review (Arlington, VA), Thursday, June 2, 2016:
    talk_2640.pdf
    Ultrafast-laser hyperdoped semiconductors have begun to be utilized for optoelectronic applications, but there is a need to better understand their fundamental physical properties. In this presentation, we discuss recent work on the basic science of ultrafast-laser structuring, time-resolved melting, resolidification, and hyperdoping, and the optical and electronic properties hyperdoped silicon. These aspects of ultrafast-laser hyperdoped semiconductors are central to hyperdoped materials science and device design.
    Laser doping and texturing of silicon for advanced optoelectronic devices, at Frontiers in Optics (FiO)/Laser Science (LS) Conference (Rochester, NY), Monday, October 17, 2016:
    talk_2641.pdf
    Irradiating a semiconductor sample with intense laser pulses in the presence of dopants drastically changes the optical, material, and electronic properties of the sample. The resulting material has applications for photodetectors and, potentially, intermediate-band solar cells.
    Innovating Education to Educate Innovators: Lessons from Physics Education Research, at 2017 AAAS Annual Meeting (Boston, MA), Friday, February 17, 2017:
    talk_2636.pdf
    Education research in the sciences began with physicists who sought to improve undergraduate education in that discipline. Physics education research (PER) established standards for evidence that increasingly have been adopted by researchers across the sciences. This presentation will provide an overview of PER, the pedagogical changes that PER has inspired in undergraduate physics courses and programs, and the implications of this work for improving undergraduate education in other disciplines.
    Less is More: Extreme Optics with Zero Refractive Index, at International School on Light Sciences and Technologies, Universidad Internacional Menéndez Pelayo (Santander, Spain), Wednesday, June 21, 2017:
    talk_2668.pdf
    Nanotechnology has enabled the development of nanostructured composite materials (metamaterials) with exotic optical properties not found in nature. In the most extreme case, we can create materials which support light waves that propagate with infinite phase velocity, corresponding to a refractive index of zero. This zero index can only be achieved by simultaneously controlling the electric and magnetic resonances of the nanostructure. We present an in-plane metamaterial design consisting of silicon pillar arrays, embedded within a polymer matrix and sandwiched between gold layers. Using an... Read more about Less is More: Extreme Optics with Zero Refractive Index
    Innovating education to educate innovators, at International School on Light Sciences and Technologies, Universidad Internacional Menéndez Pelayo (Santander, Spain), Friday, June 23, 2017:
    talk_2710.pdf
    Can we teach innovation? Innovation requires whole-brain thinking — right-brain thinking for creativity and imagination, and left-brain thinking for planning and execution. Our current approach to education in science and technology, focuses on the transfer of information, developing mostly right-brain thinking by stressing copying and reproducing existing ideas rather than generating new ones. I will show how shifting the focus in lectures from delivering information to team work and creative thinking greatly improves the learning that takes place in the classroom and promotes independent... Read more about Innovating education to educate innovators
    Less is More: Extreme Optics with Zero Refractive Index, at CLEO/Europe EQEC 2017 (Munich, Germany), Tuesday, June 27, 2017
    By simultaneously controlling the electric and magnetic properties of a nanostructured composite material (metamaterial), we can create materials with a refractive index of zero. We present a novel on-chip platform to explore zero-index metamaterials.
    Extreme optics with zero-index metamaterials, at PQE 2020, Snowbird, UT, Tuesday, January 7, 2020:
    pqe2020.pdf
    Nanotechnology has enabled the development of nanostructured composite materials (metamaterials) with exotic optical properties not found in nature. In the most extreme case, we can create materials which support light waves that propagate with infinite phase velocity, corresponding to a refractive index of zero. We have developed a variety of in-plane metamaterial designs that permit obtaining a refractive index of zero in the optical regime. We will report on some of the exotic physics of zero-index metamaterials, including strong enhancement of nonlinear optical phenomena
    Subcellular surgery and nanoneurosurgery, at CLEO-PR 2017 in Singapore, Thursday, August 3, 2017

     

    We use femtosecond laser pulses to manipulate sub-cellular structures inside live and fixed cells. Using only a few nanojoules of laser pulse energy, we are able to selectively disrupt individual mitochondria in live bovine capillary epithelial cells, and cleave single actin fibers in the cell cytoskeleton network of fixed human fibro-blast cells. We have also used the technique to micromanipulate the neural network of C. Elegans, a small nematode. Our laser scalpel can snip individual axons without causing any damage to surrounding tissue, allowing us to study the...

    Read more about Subcellular surgery and nanoneurosurgery
    Flipping your class and never looking back, at AVID at Victoria University, Melbourne, Australia, Wednesday, September 15, 2021:
    flipping_avid_vic_u.pdf

    Education is more than just transfer of information, yet that is what is mostly done in classrooms -- teachers present material (even though this material might be readily available in printed form) and for students the main purpose of classroom instruction is to take down as many notes as they can. Few students have the ability, motivation, and discipline to synthesize all the information delivered to them. Yet synthesis is perhaps the most important -- and most elusive -- aspect of education. I will show how shifting the focus in classroom learning from delivering information...

    Read more about Flipping your class and never looking back

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