physics

Less is More: Extreme Optics with Zero Refractive Index, at United States Coast Guard Academy (New London, Connecticut), Monday, October 26, 2015:
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
Subcellular surgery and nanosurgery, at Biophysics Colloquium, Elon University (Elon, NC), Friday, October 16, 2015:
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 function of individual... Read more about Subcellular surgery and nanosurgery
Less is More: Extreme Optics with Zero Refractive Index, at Physics Colloquium, Brown Univeristy (Providence, RI), Monday, September 28, 2015:
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
On-chip zero index metamaterials, at Advanced Laser Applications Workshop, Korea Institue of Machinery and Materials (Daejeon, South Korea), Friday, August 28, 2015:
Impedance-matched metamaterials with zero refractive index can be achieved by exploiting a Dirac cone at the center of the Brillouin zone. We present an in-plane Dirac-cone metamaterial consisting of low-aspect-ratio silicon pillar arrays in an SU-8 matrix with top and bottom gold layers. Using an integrated nano-scale prism constructed of the proposed material, we demonstrate unambiguously a zero refractive index in the optical regime. This design serves as a novel on-chip platform in the optical regime to explore the exotic physics of Dirac-cone metamaterials and to implement applications... Read more about On-chip zero index metamaterials
Laser doping and texturing of silicon for advanced optoelectronic devices, at 11th Conference on Lasers and Electro- Optics Pacific Rim (CLEO-PR 2015) (Busan, South Korea), Tuesday, August 25, 2015:
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 properties of these processed semiconductors make them useful for photodetectors and, potentially, intermediate band solar cells. This talk discusses the processes that lead to doping and surface texturing, which both increase the optical absorption of the material. We will discuss the properties of the resulting material including the formation of an intermediate band. We have developed laser-processed silicon... Read more about Laser doping and texturing of silicon for advanced optoelectronic devices
Manipulating light at the nanoscale (Lectures 3–5), at Nano-optics: Principles enabling basic research and applications, Centro Ettore Majorana (Erice), Thursday, July 9, 2015:
In these interactive lectures we explore how light can be manipulated at the nanoscale. We begin by describing optical propagation in ordinary materials and then show how materials can be engineered to achieve a refractive index of zero. These zero-index materials have remarkable properties and can be integrated in photonic circuits. We also give an introduction to nonlinear optics and discuss how zero-index materials can be used to accomplish phase matching in nonlinear optics.

Outline

 

  • Optical properties of materials
  • Dispersion of...
Read more about Manipulating light at the nanoscale (Lectures 3–5)
Manipulating light at the nanoscale (Lectures 1 and 2), at Nano-optics: Principles enabling basic research and applications, Centro Ettore Majorana (Erice), Wednesday, July 8, 2015:
In these interactive lectures we explore how light can be manipulated at the nanoscale. We begin by describing optical propagation in ordinary materials and then show how materials can be engineered to achieve a refractive index of zero. These zero-index materials have remarkable properties and can be integrated in photonic circuits. We also give an introduction to nonlinear optics and discuss how zero-index materials can be used to accomplish phase matching in nonlinear optics.

Outline

 

  • Optical properties of materials
  • Dispersion of...
Read more about Manipulating light at the nanoscale (Lectures 1 and 2)
Nonlinear optics at the nanoscale, at Weizmann Institute (Rehovot, Israel), Thursday, June 25, 2015:
We explore nonlinear optical phenomena at the nanoscale by launching femtosecond laser pulses into long silica nanowires. Using evanescent coupling between wires we demonstrate a number of nanophotonic devices. At high intensity the nanowires produce a strong supercontinuum over short interaction lengths (less than 20 mm) and at a very low energy threshold (about 1 nJ), making them ideal sources of coherent white-light for nanophotonic applications. The spectral broadening reveals an optimal fiber diameter to enhance nonlinear effects with minimal dispersion. We also present a device that... Read more about Nonlinear optics at the nanoscale
Inverse Transformation Optics with Realistic Material Parameters, at META'15 (New York, New York), Thursday, June 4, 2015:
We present a method to generate transformation functions based on a space of achievable material properties. To validate this approach, we consider the range of effective refractive index achievable using silver nanowires in a dielectric background. Given fabrication constraints, we generate a reduced cloaking transformation and confirm its performance using FDTD and FEM simulations. We explore conditions for finding appropriate mappings in restricted parameter spaces, and strategies for optimizing transformations to account for absorption and scattering.

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