Font Size: a A A

Design Of High Birefringent Photonic Crystal Fibers And Study On Transport Properties Of Ultrashort Laser Pulses

Posted on:2013-02-08Degree:MasterType:Thesis
Country:ChinaCandidate:X Y WangFull Text:PDF
GTID:2218330362963075Subject:Condensed matter physics
Abstract/Summary:PDF Full Text Request
Photonic crystal fibers (PCFs), expected as the typical photonic devices, will bewidely used in optical communications, optical sensing and nonlinear optics, due to theirunique adjustable characteristics and dispersion characteristics. However, the non-silicacompound glasses (ZBLAN, Telluride glass and chalcogenide glass, etc.) have a highlinear index, a nonlinear refractive index and a wide bulk transparency ranging fromnear-infrared light to the mid-infrared, so that non-silica PCFs open to broader applicationprospects. In this thesis, the characteristics of PCFs with different materials have beenstudied in detail theoretically and experimentally. The details are described as follows:Firstly, the theoretical approaches, including multipole method on electromagneticwave scattering and adaptive split-step Fourier method on transmission of ultra-shortlaser pulses, are simply introduced. And the developments on the high birefringence PCFsand supercontinuum generation are presented.Secondly, a kind of mid-infrared As2S3chalcogenide glass PCF is proposed. And thebasic characteristics of this fiber are studied by multipole method. Through numericalsimulation, it is found that the fiber can keep mid-infrared broadband normal dispersionand the perfect combination of high birefringence and high nonlinearity, which provides atheoretical basis and reference for further developments of new mid-infraredhigh-nonlinear fibers.Thirdly, the transmission of femtosecond pulse with the center wavelength of4μm inmid-infrared birefringence As2Se3chalcogenide PCF is numerically studied. The basicproperties and the transmission characteristics of this PCF are simulated by the multipolemethod and the adaptive split-step Fourier method, respectively. In addition, usingfemtosecond pulse with the center wavelength of4μm, we analyze the mechanism ofspectral broadening in the PCFs with different pitches in detailed. Especially, mid-infraredbroadband polarization supercontinuum, the width up to12μm, is obtained in a3cm longbirefringence As2Se3chalcogenide PCF.Finally, the transmission experiment on a Ti: sapphire femtosecond pulses in our self-developed PCF with birefringence and two-zero dispersion is completed, and apolarization-dependent supercontinuum spectrum source of light from the UV to infraredregion is generated. It is found that the width of the supercontinuum spectrum changesdramatically with the input polarization directions. In addition, supercontinuum spectrumgeneration, to some extent, is depended on the pump wavelength and average power of thepump. The spectrum is broadened with the increase of average power, but unchanged afteraverage power reaches a certain value; when the pump wavelength is located in theanomalous dispersion and further away from zero-dispersion wavelength, the spectrum ofthe supercontinuum is wider.
Keywords/Search Tags:Photonic crystal fibers, Birefringence, Nonlinear, Dispersion, Supercontinuum
PDF Full Text Request
Related items