STUDY OF THE AIRY PULSE PROPAGATON DYNAMICS IN DISPERSIVE AND NONLINEAR MEDIA

Abstract

Airy wave-packet has received significant interest due to its unique features including self-acceleration, self-healing and non-diffraction. Airy pulses are the temporal counterpart of this wave-packet. In this thesis, study of Airy pulse propagation dynamics in dispersive and nonlinear medium has been carried out by numerical and theoretical calculation. This study focuses on the impact of dispersion and nonlinearity on the propagation dynamics of Airy pulse that may employ as alternative way of manipulating temporal and spectral dynamics. Soliton shedding from the Airy pulse resulted from compensating the down chirp of anomalous dispersion through the Kerr nonlinearity-induced up chirp. Our investigation show that initial chirp of the input Airy pulse steer the dynamics of this emergent soliton. Chirp parameter also proves its ability of frequency tuning occurring due to the Intra pulse Raman scattering. Further, soliton shedding from Airy pulse with oscillating tail at both leading and trailing edge is achieved in presence of negative fourth-order dispersion (FOD) and focusing cubic nonlinearity. Surprisingly, the required power for soliton shedding is relatively much small. Further study disclose the role of input pulse power in manipulating the dynamics of emergent soliton with different dispersion and nonlinear effects. Time dependent optical potentials generated from co-propagating intense pump wave induce nonlinearity enabled in modifying the Airy pulse dynamics via cross-phase modulation. The implication of harmonic optical potential induced nonlinearity can be observed on weak Airy pulse dynamics resulting in soliton shedding. The initial phase of harmonic function disclose the possibility of soliton shedding from Airy pulse both in normal and anomalous dispersion. Besides, linear optical potential come up with novel avenue of controlling the dynamics of emergent soliton from Airy pulse. This study has been extended to examine the dynamics of two co-propagating pulses at different center wavelengths in dispersive and nonlinear medium. Here, emergent soliton from Airy pulse has been employed as control or pump pulse in manipulating the co-propagating pulse dynamics. In first case, we assume that both control (Airy) and signal (sech) pulse propagates in anomalous dispersive regime therefore soliton emerges from control Airy pulse that enable to affect the temporal dynamics of sech pulse depending on the initial parameters of control Airy pulse. In second case, emergent soliton from Airy pulse acts as periodic temporal boundary. Weak probe Airy pulse experiences partial reflection and transmission on encountering this periodic temporal boundary. On proper choice of initial parameters, artificial optical event horizon can be created where temporal analogue of total internal reflection is observed. In view of application prospects, investigation of Airy pulse dynamics inside a semiconductor amplifier has been carried out theoretically and compare with numerical results. This study equipped with the conclusion of the consequences of gain induced dispersion and linewidth enhancement factor of amplifier on Airy pulse acceleration. In summary, thesis provides comprehensive overview of the impact of dispersion and nonlinearity on Airy pulse propagation dynamics under various nonlinear effects and initial parameters of input pulse.