Sub-picosecond pulse break-up in an InGaAsP optical amplifier

Francis Pascal Romstad, Kashawna Harling (Editor), Xuesheng Chen (Editor)

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearch


For high speed optical communication system with data speed higher than 200 Gb/s sub-picosecond pulse dynamics, coherent effects become important.We have, experimentally and theoretically, investigated the pulse distortion of an 150 fs pulse due to amplification in a 250 ìm long InGaAsP ridge waveguide, working at 1.52 mm, for different input pulse energies.Amplitude and phase in both frequency and time domain of the initial and amplified pulse were measured using a XFROG (Cross-Frequency-Resolved Optical Gating) technique based on sum-frequency cross-correlation.Measurements show a pulse broadening and eventual break-up for input pulse energies on the order of picoJoules. This break-up is present in the gain region (6-14 dB), while for absorption (-6 dB) and transparency, pulse narrowing by a factor of two is evidenced. We observe that not only the amplitude is modulated, but also the linear chirp of the initial pulse is strongly modified.According to a numerical model, two-photon absorption and gain dispersion are responsible for the broadening and break-up. Kerr-nonlinearity at high intensities modulates the phase of the pulse and thereby the spectrum, which is evidenced in a spectral break-up. Due to gain dispersion, the spectral break-up results in a break-up in time domain.
Original languageEnglish
Title of host publicationProceedings of 16th course: Advances in Energy Transfer Processes
Number of pages34
PublisherInternatioinal School of Atomic and Molecular Spectroscopy
Publication date1999
Publication statusPublished - 1999
Event16th course International School of Atomic and Molecular Spectroscopy - Erice, Italy
Duration: 17 Jun 19991 Jul 1999
Conference number: 16


Course16th course International School of Atomic and Molecular Spectroscopy

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