Ultra-flat SPM-broadened spectra in a highly nonlinear fiber using parabolic pulses formed in a fiber Bragg grating.

We propose a new method for generating flat self-phase modulation (SPM)-broadened spectra based on seeding a highly nonlinear fiber (HNLF) with chirp-free parabolic pulses generated using linear pulse shaping in a superstructured fiber Bragg grating (SSFBG). We show that the use of grating reshaped parabolic pulses allows substantially better performance in terms of the extent of SPM-based spectral broadening and flatness relative to conventional hyperbolic secant (sech) pulses. We demonstrate both numerically and experimentally the generation of SPM-broadened pulses centred at 1542 nm with 92% of the pulse energy remaining within the 29 nm 3 dB spectral bandwidth. Applications in spectra slicing and pulse compression are demonstrated.

[1]  Inuk Kang,et al.  Simultaneous temporal characterization of telecommunication optical pulses and modulators by use of spectrograms. , 2002, Optics letters.

[2]  B C Thomsen,et al.  Self-similar propagation and amplification of parabolic pulses in optical fibers. , 2000, Physical review letters.

[3]  Masataka Nakazawa,et al.  Parabolic pulse generation by use of a dispersion-decreasing fiber with normal group-velocity dispersion. , 2004, Optics letters.

[4]  Magnus Karlsson,et al.  Wave-breaking-free pulses in nonlinear-optical fibers , 1993 .

[5]  Y. Takushima,et al.  10-GHz, over 20-channel multiwavelength pulse source by slicing super-continuum spectrum generated in normal-dispersion fiber , 1999, IEEE Photonics Technology Letters.

[6]  Cyril Billet,et al.  Experimental generation of parabolic pulses via Raman amplification in optical fiber. , 2003, Optics express.

[7]  P. Petropoulos,et al.  Pulse retiming based on XPM using parabolic pulses formed in a fiber Bragg grating , 2006, IEEE Photonics Technology Letters.

[8]  J. Fujimoto,et al.  Ultrahigh-resolution optical coherence tomography using continuum generation in an air-silica microstructure optical fiber. , 2001, Optics letters.

[9]  Comparison between nonlinear and linear spectrographic techniques for the complete characterization of high bit-rate pulses used in optical communications , 2005, IEEE Photonics Technology Letters.

[10]  Hall,et al.  Direct link between microwave and optical frequencies with a 300 THz femtosecond laser comb , 2000, Physical review letters.

[11]  J W Nicholson,et al.  All-fiber, octave-spanning supercontinuum. , 2003, Optics letters.

[12]  C. Billet,et al.  Intermediate asymptotic evolution and photonic bandgap fibre compression of optical similaritons around 1550 nm , 2005, CLEO/Europe. 2005 Conference on Lasers and Electro-Optics Europe, 2005..