University of Connecticut

Events Calendar

PhD Dissertation Defense

Wednesday, August 3, 2022
11:00am – 1:00pm


Graduate Student Sunil Thapa, Department of Physics, University of Connecticut

Study Of High Repetition Rate Ultrashort Pulses and its Application on Data Encryption

Optical communication progress has been attributed to time division multiplexing (TDM) and dense wavelength division multiplexing (DWDM). These methods use broadband light source and ultrashort pules with high repetition rate to carry information on optical fibers. The solution to high data traffic demands in future will be ultrafast data processing switching components as conventional electro-optical process efficiency and speed has reached it bottleneck. In this PhD dissertation, an erbium doped fiber ring laser with graphene as a saturable absorber has been designed and this ring laser system is able to generate ultrashort pulses with a repetition rate of 50 GHz. This method produces pulses with narrow width compared to conventional rational harmonic mode locking technique. Effects of two-photon absorption (TPA) on all-optical logic operation in quantum-dot semiconductor optical amplifier (QD-SOA) has been carried out. Inclusion of two photon absorption improves the Q-factor for pseudorandom bit generation (PRBS) at high-speed operation. High speed all-optical encryption operation at 320 Gb/s using optical logic gates which is based on QD-SOA with two photon absorption has been demonstrated. Supercontinuum generation using different shape of dispersion varying waveguides has also been simulated. The non-uniform waveguide allows for continuous phase matching to generate broader spectrum.

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Prof. N. Dutta

Physics Department (primary), College of Liberal Arts and Sciences, UConn Master Calendar

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