Supercontinuum generation in optimized photonic crystal fiber at 1.3 μm for optical coherence tomography

Abstract

In this paper, we have designed a high nonlinear photonic crystal fiber (HN-PCF) based on square-lattice geometry with the zero dispersion wavelength (ZDW) around 1300 nm. The exploitation of different nonlinear mechanisms in the pulse propagation allows supercontinuum generation, which is used to enhance the axial resolution of the optical coherence tomography (OCT) systems. First mechanism demonstrated is the soliton self-compression, we came up to realize pulse compression of 28.4 fs around 1300 nm by the generation of solitons of different orders to obtain ultrashort pulses of about 4 fs pulses in a PCF length of 66cm, then, we improved the pulse compression until 1.2 fs in a PCF length of 26 cm.The exploitation of the interplay between many nonlinear effects as self-phase modulation, intrapulse Raman scattering and self-steepening as second mechanism allows a generation of supercontinuum with a spectral bandwith of SBW=260 nm. The obtained spectral bandwidth could contribute to enhance the OCwith OCT imaging axial resolution which can be evaluated to 2.8 μm in air, working at 1.3 μm center wavelength which is widely used in several fields.