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We fabricate waveguides in Corning® flexible glass using Femtosecond Laser Micromachining (FLM) and visualize the ultrafast plasma dynamics which lead to waveguide formation via time-resolved interferometry. Due to minimal thermal effects and highly-nonlinear optical processes [1], FLM is an ideal tool to fabricate waveguides in glass with high precision and without post processing. We optimize laser fabrication of waveguides by varying scanning speed and pulse energy and, in particular, achieve waveguides with circular cross-sections using slit beam shaping [2]. Further optimization requires investigation of the underlying dynamics of how structural changes in glass are made during and after laser-glass interactions. Thus, we visualize the creation and recombination of plasma in glass which leads to the formation of waveguides using time- resolved interferometry [3]. [1] Rafael R. Gattass and Eric Mazur, Nature Photonics 2, 219–225 (2008)); [2] M. Ams et al. Opt. Express 13, 5676-5681 (2005); [3] G. C. Nagar, D. Dempsey, and B. Shim, Communications Physics 4, 96 (2021).
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Photo-induced ultrafast dynamics and non-linear processes in molecules
Understanding the dynamics of various photo-induced physical and chemical processes in molecules is fundamental to physics, chemistry, and biology. These dynamics, which occur on pico- and femtosecond scales, are observable using ultrafast tools like ultrashort laser pulses that can be generated using tabletop laser and free-electron lasers. This thesis systematically studies some of these processes using different light sources and probing techniques, revealing new physics and offering insights into potential future control of these phenomena.
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- Award ID(s):
- 2306982
- PAR ID:
- 10584004
- Publisher / Repository:
- University of Connecticut
- Date Published:
- Subject(s) / Keyword(s):
- Ultrafast, Molecular Dynamics
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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