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Modal and Material Dispersion. Daniil Y. Gladkov. Outline. Hardware Types of Dispersion Data Transfer Function Future Project Proposals. Why does dispersion matter ?.
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Modal and Material Dispersion Daniil Y. Gladkov
Outline • Hardware • Types of Dispersion • Data • Transfer Function • Future Project Proposals
Why does dispersion matter ? • Understanding the effects of dispersion in optical fibers is quintessential in optical communications in order to minimize pulse spreading. • Pulse compression due to negative dispersion can be used to shorten pulse duration in chirped pulse lasers
Pulsed Fiber Laser System From Wesley Hughes and Jared Green’s Presentation
Modal Dispersion • Pulse Spreading: where • Number of modes: where • Fiber Used: ,
Material Dispersion • Pulse Spreading: • Dispersion Coefficient:
Anomalous Dispersion • Pulse’s higher frequency have faster phase velocity than the lower frequency components • Responsible for negative dispersion, pulse compression, and soliton formation • http://www.falstad.com/dispersion/normal.html
1km, 2km, 3km Fiber with Femtosecond Pulse Laser Results • 1 km - pulse width: 215 psσ: 572ps • 2 km - pulse width: 385 psσ: 2.4ps • 3 km - pulse width: 382 psσ: 1.62ps • Results do not agree with theory
Suggestions for Future Projects • Use Optical amplifier to boost output signal • Spectral profiling of pulses • Anomalous Dispersion modeling • Better fitting and transfer function modeling • High powered laser to overcome attenuation • More variations of fiber lengths • Soliton formation