Abstract

Generation of optical pulses at repetition rates in 10s-100s GHz range beyond the limits of conventional electronics can be achieved using all optical passive techniques. Here, we report a 60 GHz soliton pulse source utilizing all optical fibre technology. The principle of operation is based on the use of dual frequency beating as a source of periodic optical signal and the transformation of the beat half-periods into optical pulses using nonlinear propagation in a novel optical fibre design which we call a Comblike Dispersion Profiled Fibre (CDPF). This fibre consists of many alternating segments of two fibre types with high anomalous dispersion and minimum absolute dispersion at the operational wavelength. In fact, the dispersion-length profile of this fibre has a comb-like shape. Previously, transformation of the optical beat signal into pulse train was demonstrated in a Dispersion Decreasing Fibre (DDF) [1]. However, the implementation of CDPF has a number of advantages: CDPF can provide significant suppression of Stimulated Brillouin Scattering (SBS) enabling the use of a narrow linewidth, low phase noise beat signal; it can provide pulse train generation over a much wider range of repetition rates and a reduction of the necessary input power; and a CDPF can be accurately produced with in advance determined properties using conventional standard types of optical fibres - Standard Telecommunication (STF) and Dispersion Shifted Fibres (DSF) and thus does not require any special technology.

© 1993 Optical Society of America