Femtosecond laser micromachining: Applications in Technology and Biology, at The 8th International Conference on Laser Ablation (Banff, Canada), Monday, September 12, 2005:
When femtosecond laser pulses are tightly focused into a transparent material, the intensity in the focal volume is high enough to cause absorption through nonlinear processes. The absorption of the laser energy excites a submicrometer-sized region of plasma inside the material, and the energy is subsequently transferred to the atoms in the form of heat and shock waves. This process permanently alters solids and ablates cellular structures in biological media [1]. Applications include high-density data storage in three dimensions, writing of waveguides and waveguide splitters in bulk glass,... Read more about Femtosecond laser micromachining: Applications in Technology and Biology
Visualization and visual illusions: how the mind tricks us, at Mazur/Rogers/Cambridge Public School District Fair, Harvard University (Cambridge, MA), Wednesday, August 31, 2005:
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.
Visual learning: how much do we learn from what we see?, at AAPT Summer Meeting (Salt Lake City, UT), Wednesday, August 10, 2005:
Classroom demonstrations and textbook illustrations are often considered to be key tools in improving student understanding of physical concepts. Vizualization alone, however, does not necessarily improve student understanding and can even create additional misconceptions. Active engagement of the students is essential to avoid the creation of a “wrong picture”.
Technology for Peer Instruction, at AAPT Summer Meeting (Salt Lake City, Utah), Tuesday, August 9, 2005:
The Interactive Learning Toolkit (ILT) is a tool to implement innovative teaching ideas such as Peer Instruction and Just in Time Teaching, and to monitor students’ learning. It incorporates a large Concept Test (CT) database and provides the opportunity to easily integrate CTs into lectures. This talk will discuss the integration of the content management of the ILT with the Interactive Classroom features of BQ, a software developed at Erskine College. Student responses using IR clickers, wireless laptops, PDAs and cell phones are combined to give the instructor immediate feedback on student... Read more about Technology for Peer Instruction
Wrapping light around a hair, at Harvard Crimson Summer Academy Meeting, Harvard University (Cambridge, MA), Wednesday, July 13, 2005:
Can light be guided by a fiber whose diameter is much smaller than the wavelength of the light? Can we mold the flow of light on the micrometer scale so it wraps, say, around a hair? Until recently the answer to these questions was ‘no’. We developed a technique for drawing long, free-standing silica wires with diameters down to 50 nm that have a surface smoothness at the atomic level and a high uniformity of diameter. Light can be launched into these silica nanowires by optical evanescent coupling and the wires allow low-loss single-mode operation. They can be bent sharply, making it... Read more about Wrapping light around a hair
Femtosecond laser dissection of neurons in C. elegans, at NATO ASI Course on New developments in optics and related fields: modern techniques, materials, and applications, Centro Ettore Majorana (Erice, Italy), Tuesday, June 14, 2005:
Tightly-focused femtosecond laser pulses of a few nanojoules sever individual dendrites in the nematode worm C. elegans. Quantification of the resulting behavioral deficits identifies the contribution of the dissected structures. Due to nonlinear absorption of laser light, the dissection has submicrometer resolution with no collateral damage, permitting subcellular surgery on live animals. Future work include an examination of the molecular basis of neurodegeneration that has application to diseases such as Parkinsons and Alzheimers.
Optoelectronic devices using femtosecond laser microstructured silicon, at NATO ASI Course on New developments in optics and related fields: modern techniques, materials, and applications, Centro Ettore Majorana (Erice, Italy), Sunday, June 12, 2005:
Arrays of sharp, conical microstructures are obtained by stucturing the surface of a silicon wafer using femtosecond laser-assisted chemical etching. The one step, maskless structuring process drastically changes the optical, material and electronic properties of the original silicon wafer. These properties make microstructured silicon viable for use in a wide range of commercial devices including solar cells, infrared photodetectors, chemical and biological sensors, and field emission devices.