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2001

Laser induced microexplosions and applications in laser micromachining, at Annual Meeting of the Stanford Photonics Research Center, Standord University (Palo Alto, CA), Saturday, September 15, 2001:
talk_400.pdf
When femtosecond laser pulses are focused tightly into a transparent material, the intensity in the focal volume can become high enough to cause nonlinear absorption of laser energy. The absorption, in turn, can lead to permanent structural or chemical changes. Such changes can be used for micromachining bulk transparent materials. Applications include data storage and the writing of waveguides and waveguide splitters in bulk glass, fabrication of micromechanical devices in polymers, and subcellular photodisruption inside single cells. In this talk we will review recent results obtained in... Read more about Laser induced microexplosions and applications in laser micromachining
Visible luminescence of silicon microstructures fabricated with femtosecond-laser irradiation, at International School of Atomic and Molecular Spectroscopy, Ettore Majorana Center for Scientific Culture (Erice, Sicily, Italy), Saturday, June 23, 2001:
talk_398.pdf
We report visible luminescence from SiOx formed by microstructuring silicon with femtosecond laser pulses in air. Incorporation of oxygen into the silicon lattice occurs only where the laser beam strikes the surface. Laser-structuring therefore offers the possibility to write luminescent submicron features without the use of masks. The amount of oxygen incorporated depends on the laser fluence used for microstructuring. The peak wavelength of the primary luminescence band varies between 540 and 630 nm and depends on the number of laser shots used for microstructuring. Upon annealing, the... Read more about Visible luminescence of silicon microstructures fabricated with femtosecond-laser irradiation
Innovations that work in large physics courses: why and how?, at Astronomy Department Chairs Meeting, Harvard University (Cambridge, MA), Friday, June 15, 2001:
talk_385.pdf
Education is more than just transfer of information, yet that is what is mostly done in large introductory courses -- instructors present material (even though this material might be readily available in printed form) and for students the main purpose of lectures 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. Students get frustrated because they are unable to grasp simple concepts. Instructors get... Read more about Innovations that work in large physics courses: why and how?
Black silicon: hot properties and many open questions, at Atomic and molecular physics at surfaces, ITAMP (Cambridge, MA), Thursday, June 14, 2001:
talk_388.pdf
A serendipitous discovery in our lab produced a novel form of microstructured silicon ("black silicon") that has many surprising properties: near unity absorption, even below the bandgap; production of photoelectrons in the visible and infrared; visible luminescence; and a strong field emission current. We are beginning to shed light on what might cause some of the material's remarkable properties. Much additional experimental and theoretical work is required to understand the surface physics and chemistry that leads to the formation of black silicon.
Assessing the initial state of knowledge of first-year genetics students, at ASM Eighth Undergraduate Microbiology Education Conference, American Society for Microbiology (Orlando, FL), Saturday, May 19, 2001:
talk_384.pdf
A survey was designed to assess students' understanding of concepts and familiarity with biology terminology at the beginning of a new introductory genetics course. The class, which serves as the first college biology course for all students majoring in Biological Sciences or fulfilling premedical requirements, assumes no prior knowledge and enrolls mainly first-year students. The survey asked students to rate their familiarity with over 80 words in genetics and to define a selection of these terms. Students were also asked to answer a few conceptual questions as well as provide background... Read more about Assessing the initial state of knowledge of first-year genetics students
Micromachining and laser processing with ultrashort laser pulses, at Second International Symposium on Laser Precision Microfabrication (LPM2001) (Singapore), Wednesday, May 16, 2001:
talk_359.pdf
When femtosecond laser pulses are focused tightly into a transparent material, the intensity in the focal volume can become high enough to cause nonlinear absorption of laser energy. The absorption, in turn, can lead to permanent structural or chemical changes. Such changes can be used for micromachining bulk transparent materials. Applications include data storage and the writing of waveguides and waveguide splitters in bulk glass, fabrication of micromechanical devices in polymers, and subcellular photodisruption inside single cells. In this talk we will review recent results obtained in... Read more about Micromachining and laser processing with ultrashort laser pulses

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