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2009

Nano hemi-shell arrays produced by femtosecond laser micro-processing for SERS applications, at Photonics West 2009 (San Jose, CA), Tuesday, January 27, 2009
Nano-scale periodic structures produce a greatly enhanced near-field at the surface and therefore they are very promising for applications involving Surface Enhanced Raman Scattering (SERS). The ideal shape of the structure is a sphere, a rod, a needle or a hemi-shell. Nano hemi-shell structures obtained by evaporating a thin metal film on small dielectric particles, in particular, have attracted much attention, because their resonant wavelength can be easily tuned by controlling the thickness of the metal film, shells diameter, or the distance between particles. Furthermore, the dielectric... Read more about Nano hemi-shell arrays produced by femtosecond laser micro-processing for SERS applications
Femtosecond laser doping of silicon beyond the equilibrium limit, at Photonics West 2009 (San Jose, CA), Tuesday, January 27, 2009:
talk_1443.pdf
Shining intense, ultrashort laser pulses on the surface of a crystalline silicon wafer drastically changes the optical, material and electronic properties of the wafer. The resulting textured surface is highly absorbing and looks black to the eye. The properties of this 'black silicon' make it useful for a wide range of commercial devices. In particular, we have been able to fabricate highly-sensitive PIN photodetectors using this material. The sensitivity extends to wavelengths of 1600 nm making them particularly useful for applications in communications and remote sensing.
Peer Instruction: workshop -- technology, at Seminario Internacional sobre la Enseñanza y Aprendizaje Efectivo, Universidad Adolfo Ibáñez (Santiago, Chile), Tuesday, January 20, 2009:
talk_1428.pdf
It has been suggested the lack of interaction in large lecture courses is to blame for the many problems facing these courses: declining enrollments, low attendance, poor evaluations, and disappointing retention. We offer a way of redesigning the classroom so interaction is introduced in many aspects of the course. This approach has shown to be effective by many instructors in a broad variety of environments. I will demonstrate some of the tools we have developed to foster this interaction.
How the mind tricks us: visualizations and visual illusions, at Seminario Internacional sobre la Enseñanza y Aprendizaje Efectivo, Universidad Adolfo Ibáñez (Santiago, Chile), Tuesday, January 20, 2009:
talk_1429.pdf
Neurobiology and cognitive psychology have made great progress in understanding how the mind processes information – in particular visual information. The knowledge we can gain from these fields has important implications for the presentation of visual information and student learning
Confessions of a converted lecturer, at Seminario Internacional sobre la Enseñanza y Aprendizaje Efectivo, Universidad Adolfo Ibáñez (Santiago, Chile), Monday, January 19, 2009:
talk_1425.pdf
I thought I was a good teacher until I discovered my students were just memorizing information rather than learning to understand the material. Who was to blame? The students? The material? I will explain how I came to the agonizing conclusion that the culprit was neither of these. It was my teaching that caused students to fail! I will show how I have adjusted my approach to teaching and how it has improved my students' performance significantly
The scientific approach to teaching: Research as a basis for course design, at Seminario Internacional sobre la Enseñanza y Aprendizaje Efectivo, Universidad Adolfo Ibáñez (Santiago, Chile), Monday, January 19, 2009:
talk_1426.pdf
Discussions of teaching -- even some publications -- abound with anecdotal evidence. Our intuition often supplants a systematic, scientific approach to finding out what works and what doesn't work. Yet, research is increasingly demonstrating that our gut feelings about teaching are often wrong. In this talk I will discuss some research my group has done on gender issues in science courses and on the effectiveness of classroom demonstrations.
Peer Instruction: workshop, at Seminario Internacional sobre la Enseñanza y Aprendizaje Efectivo, Universidad Adolfo Ibáñez (Santiago, Chile), Monday, January 19, 2009:
talk_1427.pdf
The basic goals of Peer Instruction are to encourage and make use of student interaction during lectures, while focusing students' attention on underlying concepts and techniques. The method has been assessed in many studies using standardized, diagnostic tests and shown to be considerably more effective than the conventional lecture approach to teaching. Peer Instruction is now used in a wide range of science and math courses at the college and secondary level. In this workshop, participants will learn about Peer Instruction, serve as the “class” in which Peer Instruction is demonstrated,... Read more about Peer Instruction: workshop
Optically hyperdoped silicon, at The 39th Winter Colloquium on the Physics of Quantum Electronics (Snowbird, UT), Thursday, January 8, 2009:
talk_1424.pdf
By irradiating silicon with a train of femtosecond laser pulses in the presence of chalcogen (column VI) compounds, a thin layer of Si is doped to previously unreported, non-equilibrium levels (about 2%). This optical hyperdoping (OHD) process creates a highly absorbing surface and extends silicon’s spectral sensitivity, even for infrared photons with energy less than the band gap. The optoelectronic properties of this 'black silicon' make it useful for a wide range of commercial devices in communications, remote sensing, and solar energy harvesting. Prototype OHD silicon photodiodes exhibit... Read more about Optically hyperdoped silicon

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