Presentations

    Raman spectroscopy of infrared multiphoton excited molecules, at XIVth Int. Quantum Electronics Conf. (San Francisco, CA), Wednesday, January 1, 1986
    Anti-Stokes signals from various modes of isolated, infrared multiphoton excited SF6 and C2H4F2 molecules are measured as a function of pressure, infrared fluence and wavelength. This allows to verify whether intramolecular equilibrium of vibrational energy is established after infrared multiphoton excitation in isolated molecules.
    Multiplex CARS study of infrared-multiphoton-excited OCS, at Ninth International Conference on Laser Spectroscopy (Bretton Woods, NH), Thursday, June 1, 1989
    The vibrational energy distribution following the ?2 overtone excitation of OCS by a pulsed CO2 laser can be studied by coherent anti-Stokes Raman spectroscopy (CARS) of the ?1 mode. Since the anharmonicity of the pumped mode is small, and since the relaxation to other modes is slow, OCS allows one to study the interaction of an isolated harmonic mode with an intense laser field. Single-shot spectra are obtained by using a broadband dye laser and recording the CARS signal on a multichannel analyzer. The phase matching of the beams is done in a so-called folded boxcars arrangement. The... Read more about Multiplex CARS study of infrared-multiphoton-excited OCS
    Factors affecting gender disparity in introductory physics, at APS Centennial Meeting 1999 (Atlanta, GA), Tuesday, March 23, 1999:
    In America, the disparity between the performance of women and men in physics is a matter of common concern; however, it is poorly understood. Is this disparity observed among physics majors at elite institutions as well as non-majors in one-year introductory courses? Does this disparity depend on the pedagogical approach used to teach the class? The high school physics or mathematics background of the students? The gender of the instructor?
    Determining properties of spindle microtubules with femtosecond nanosurgery, at BiOS 7897, SPIE Photonics West (San Francisco, CA), Monday, January 24, 2011
    In eukaryotic cells, the spindle ensures the faithful segregation of the genetic material during cell division. In this study we use femtosecond nanosurgery to quantitatively measure parameters describing the metaphase spindle. We selectively cut microtubules of metaphase spindles assembled from Xenopus egg extracts. After the cut, microtubules depolymerize rapidly. Analysis of the time-lapse imaging reveals the depolymeration dynamics and allows determining the length distribution of the microtubules. We show that the average length of microtubules in metaphase spindles increases from the... Read more about Determining properties of spindle microtubules with femtosecond nanosurgery
    Black silicon: A new light absorber for photovoltaic applications, at APS Centennial Meeting 1999 (Atlanta, GA), Tuesday, March 23, 1999:
    We demonstrate a new technique for texturing silicon surfaces using femtosecond laser pulses. Sharp micron-sized spikes are created by repeatedly irradiating a silicon surface with femtosecond laser pulses in the presence of SF6. The spikes are highly light-absorbing and enhance the light absorption in silicon close to 100 (increase in photocurrent of more than 60) over flat silicon. Spiked silicon is of potential use as a highly efficient light-absorber for solar cells and photodetectors.
    Light scattering from nonequilibrium liquid interfaces, at Tenth Symposium on Thermophysical Properties (Gaithersburg, MD), Wednesday, June 1, 1988
    The asymmetry of the two Brillouin peaks of light scattered from capillary waves on a water-nitrogen interface subject to a temperature gradient has been observed using a Fourier transform heterodyne technique. The local oscillator is frequency-shifted by a few kHz to separate the Stokes and anti-Stokes components. Although the sign and the order of magnitude of the effect agree with linear theory, the magnitude of the experimental asymmetry is about one half of the one predicted by linear fluctuating hydrodynamics.
    Fourier transform heterodyne spectroscopy of liquid interfaces, at Conference on Laser Materials and Laser Spectroscopy '88 (Shanghai, People's Republic of China), Friday, July 1, 1988
    By acousto-optically shifting the local oscillator in a heterodyne set-up, a spectral resolution of better than 150 mHz can be obtained. Applications of the technique to the study of interfacial phenomena are discussed.
    Laser melting of silicon: the first few picoseconds, at Annual Meeting of the Electrochemical Society (Chicago, IL), Saturday, October 1, 1988
    The use of a streak camera makes it possible to improve the study of the melting of silicon during picosecond laser annealing. Its time resolution of 1.8 ps enables us to confirm that the molten silicon is heated above the melting temperature. It also provides spatial information on the melting process.

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