Spectral, temporal and vectorial properties of ultrafast optical pulse propagating in optical fibers

The polarization state of light is important for applications and experimental work of the light propagating in optical fibers. In this thesis, a theoretical model for intense laser light pulses propagating in nonbirefringent single-mode optical fibers has been proposed for the first time. Polarization stabilities of linearly and circularly polarized laser pulses propagating in nonbirefringent single-mode optical fibers are analyzed. Nonlinear depolarization and polarization rotation for linearly polarized laser pulses in optical fibers are calculated. The changes of the temporal properties of the propagating laser pulses in single-mode optical fibers are also discussed.;The polarization stabilities for linearly and circularly polarized ultrashort laser pulses propagating in nonbirefringent single-mode fibers were measured. The experimental results and analytical conclusions are in good agreement. Picosecond laser pulses with a duration of 35 ps were used to observe the polarization stabilities of Linearly and circularly polarized light pulses.;Nonlinear polarization twisting (NPT) of linearly polarized laser light pulses has been studied using picosecond and femtosecond laser plight pulses propagating in nonbirefringent single-mode optical fibers. The theoretical simulation of the NPT are in good agreement with the measured results. Nonlinear polarization rotation and depolarization which occurred due to the NPT of linearly polarized light pulses were measured using femtosecond laser light pulses propagating in nonbirefringent single-mode optical fibers. The femtosecond light pulses from a Ti:sapphire laser system had a pulse duration of 120 fs at the wavelength of 780 nm.;The single pulse degenerate cross-phase modulation (DXPM) was measured for its two circularly polarized components of ultrashort laser pulses in single-mode optical fibers. The experimental results has shown that the DXPM process should be considered even for a single laser pulse propagating in an single-mode optical fiber. This result is quiet different with the conventional understanding on XPM in which XPM was thought only to occur between two separated laser pulses.;The DXPM of two physically separated light pulses was investigated for different time delays and pulse intensities in a nonbirefringent single-mode optical fiber. Considering the nonlinear polarization stability of circularly polarized light, two opposite-rotating circularly polarized light pulses were used in the experiment. The DXPM process for light in different modes in a multi-mode optical fiber was also studied in the thesis work. Laser light was coupled into the lowest two propagation modes in a multi-mode fiber (LP...