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Fabrication of Structured Nanocomposite Materials for Three-Dimensional Metamaterial Applications, at MRS Fall Meeting 2012 (Boston, MA), Wednesday, November 28, 2012
Fabrication of Structured Nanocomposite Materials for Three-Dimensional Metamaterial Applications We present a technique that combines top-down and bottom-up nanofabrication approaches to create a structured nanocomposite material. The structured nanocomposite material consists of three-dimensional (3D) silver nanostructures embedded inside a doped polymer matrix. The positioning of silver structures within the matrix is controlled via femtosecond laser irradiation. The key is to use a material combination that yields a stable background dielectric matrix while allowing nanostructure growth... Read more about Fabrication of Structured Nanocomposite Materials for Three-Dimensional Metamaterial Applications
Peer Instruction Network, at Physics Education Research Mini Conference, Harvard University (Cambridge, MA), Friday, November 16, 2012:
talk_2037.pdf
Teaching within an academic research career is often cast as a private enterprise, representing a silo among professors’ more communal work within research groups and service activities. Just like new frontiers in science research, innovation in science education rarely happens in isolation, more often it occurs through joint ventures. In this presentation, we introduce Peer Instruction Network, a new social network developed at Harvard University to connect educators worldwide in their efforts to shape the terrains of how and what people learn in the 21st century. The presentation will... Read more about Peer Instruction Network
Mid-infrared absorptance of silicon hyperdoped with chalcogens via fs-laser irradiation, at Black Silicon Symposium (Albany, NY), Thursday, August 9, 2012:
talk_1972.pdf
Silicon hyperdoped with heavy chalcogen atoms via femtosecond-laser irradiation exhibits strong broadband absorption. Understanding this absorption could enable applications for infrared detection and the intermediate band photovoltaic effect. In this work, we extend absorption measurements to wavelengths >14 μm using Fourier transform infrared spectroscopy and study sulfur-, selenium- or tellurium-hyperdoped Si before and after annealing. We find that the surface morphology of the sample significantly influences the extent of absorption into the mid-infrared wavelength range.... Read more about Mid-infrared absorptance of silicon hyperdoped with chalcogens via fs-laser irradiation
Turn to your neighbor, at Turning Technology User Conference: Aarhus, Denmark, Aarhus University (Aarhus, Denmark), Tuesday, June 19, 2012:
talk_1951.pdf
Peer Instruction (PI) is a teaching method that leverages the power of cutting-edge learning technologies, such as clickers, to transform learning. The centerpiece of Peer Instruction is the ConcepTest, a short interactive question that helps uncover student misconceptions. “Turn to your neighbor” is the classic catch-phrase of PI methodology, whereby teachers encourage students to think about a question, vote on their answer, and then turn to their neighbor to engage, rather than sitting passively in a lecture. In this presentation, we examine two big, open questions frequently posed by... Read more about Turn to your neighbor
Science pedagogy - no longer a private frontier, at Frontiers in Science Teaching, Aarhus University (Aarhus, Denmark), Monday, June 18, 2012:
talk_1950.pdf
Teaching within an academic research career is often cast as a private enterprise, representing a silo among professors’ more communal work within research groups and service activities. Just like new frontiers in science research, innovation in science education often involves joint ventures. In this presentation, we introduce for the first time Peer Instruction Network, a new social network developed at Harvard University to connect educators worldwide in their efforts to shape the terrains of how and what people learn in the 21st century. The presentation will include a live... Read more about Science pedagogy - no longer a private frontier
Classroom Response Systems at Harvard FAS: Status and Trends, at Harvard IT Summit, Harvard University (Cambridge, MA, USA), Thursday, May 31, 2012:
talk_1946.pdf
The presentation will describe Harvard University Information Technology’s experience of supporting the Turning Technologies classroom response system for FAS courses after more than two years. It will also include recent developments about Learning Catalytics, new software developed by Eric Mazur’s team that allows instructors to go beyond multiple-choice questions and to manage the interactive classroom through peer instruction. The audience will have the opportunity to experience Turning Technologies and Learning Catalytics firsthand during the presentation.
Submicrometer-width TiO2 waveguides, at CLEO (San Jose, CA), Monday, May 7, 2012:
talk_1961.pdf
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.
Femtosecond-laser hyperdoping: controlling sulfur concentrations in silicon for band gap engineering, at APS March meeting (Boston, MA), Tuesday, February 28, 2012:
talk_1895.pdf
Doping silicon to concentrations above the metal-insulator transition threshold yields a novel material that has potential for photovoltaic applications. By focusing femtosecond laser pulses on the surface of a silicon wafer in a sulfur hexafluoride (SF6) environment, silicon is doped with 1% atomic sulfur. This material exhibits near-unity, broadband absorption from the visible to the near infrared (< 0.5 eV, deep below the silicon bandgap), and metallic-like conduction. These unusual optical and electronic properties suggest the formation of an intermediate band. We report on the... Read more about Femtosecond-laser hyperdoping: controlling sulfur concentrations in silicon for band gap engineering

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