Sub-picosecond pulse generation employing an SOA-based nonlinear polarization switch in a ring cavity

Abstract

Abstract:We demonstrate the generation of sub-picosecond optical pulses using a semiconductor optical amplifier (SOA) and a linear polarizer placed in a ring-laser configuration. Nonlinear polarization rotation in the SOA serves as the passive mode-locking mechanism. The ring cavity generates pulses with duration below 800 fs (FWHM) at a repetition rate of 14 MHz. The time -bandwidth product is 0.48. Simulation results in good agreement with the experimental results are presented. ©2004 Optical Society of America

Tunable multiwavelength SOA fiber laser with ultra-narrow wavelength spacing based on nonlinear polarization rotation

“…The laser output is extracted from the cavity by a 10/90 fiber coupler, with which 90% power is fed back into the laser. The part surrounded by dashed lines is a general configuration of nonlinear polarization rotation in a SOA, which has been used for optical signal processing [12] and passive mode-locking [13]. The output is measured by an optical spectrum analyzer (ANDO AQ6317, resolution 0.01nm).…”

“…So the SOA cannot support the multiwavelength geneneration with wavelength spacing as small as 0.08 nm. Note that the self-induced polarization rotation in the SOA has been utilized to mode-lock fiber laser and optical signal processing with nonlinear phase-shift created in the SOA and polarization discriminated in the polarizer [12,13]. In these cases, the output from the combination of a SOA and a polarizer increase with the incoming light intensity.…”

All-optical flip-flop memory using SOA-based modelocked ring lasers with optical feedback

“…Active modelocking using phase modulation in a SOA ring laser is implemented, while the details are described in [6]. The cavity also contains a nonlinear polarisation switch, which acts as an additional pulse compression element [7]. It will be shown that the ring laser outputs pulses with a duration of 1.5 ps (full width at half maximum, FWHM) at a repetition rate of 10 GHz.…”

“…An essential building block in the cavity was a nonlinear polarisation switch that acted as a pulse compression element to compensate the dispersion in the fibre. Details concerning the nonlinear polarisation switch can be found in the context of passive modelocking in [7]. Shorter pulsewidth allows the flip-flop to be employed in higher OTDM bit-rate systems.…”

Passive Mode Locking of Lasers by Crossed-Polarization Gain Modulation

“…The technological difficulties of making faster absorbers stimulated the search for ''artificial'' saturable absorbers which are characterized by ultrafast intensity-dependent losses, e.g., additive-pulse ML, nonlinear polarization rotation (NLPR), and Kerr lens mode locking (KLM) [4]. Among these methods, NLPR takes advantage of the lightwave polarization degree of freedom and it has recently been demonstrated in ML semiconductor lasers [5].…”