Compression of pulses from soliton fibre lasers in a dispersion decreasing fibre

We report high-quality adiabatic compression of 2-4 psec pulses from a passive all-fibre soliton ring laser operating at 1550 nm down to 250 fsec in a 1.6 km dispersion decreasing fibre (DDF). Compression of 600 fsec solitons from a figure-8 fibre laser down to 100 fs in a 100m DDF was also obtained.<br/

Soliton pulse compression in dispersion decreasing fibre

We investigate the adiabatic compression of picosecond and subpicosecond soliton pulses from all-fiber, passively mode-locked, erbium-doped fiber soliton lasers operating at 1550 nm in dispersion-decreasing fibers (DDF's). High-quality soliton compression from 630 down to 115 fs in a 100-m DDF and from 3.5 down to 230 fs in a 1.6-km DDF is obtained. The effects of third-order dispersion and Raman self-scattering on the compression process are observed and discussed

114Gbit/s soliton train generation through Raman self-scattering of a dual frequency beat-signal in dispersion decreasing optical fibre

We report the generation of 114 Gbit/s trains of 250 fs fundamental solitons. The pulses are generated due to the conversion of an intense optical beat signal (generated from two DFB laser diodes and an erbium doped fiber amplifier combination) into a soliton train due to nonlinear propagation in a 1.6 km fiber of steadily decreasing dispersion. The train repetition rate corresponds to the beat frequency of the input signal and was readily tunable between 80 and 120 GHz. The results of a computer simulation of the system are found to be in good qualitative agreement with the experimental observations

CW soliton train generation in the repetition rate range 60-90GHz using a dispersion decreasing fibre

We report the generation of stable, CW soliton trains at 1.551µm using a technique based on the nonlinear propagation of a beat-signal in a dispersion-tailored fibre system. Repetition rates in the range 60-90 Gbit/s and mark-space ratios in the range 1:5 to 1:11 were obtained

Use of agroecological soil monitoring data in designing adaptive landscape farming systems

The article analyzes the experience of using agroecological monitoring data in designing adaptive landscape systems of agriculture and soil protection in the Belgorod region. On the basis of data on soil acidity, design and estimate documentation for liming is developed. Materials on the content of soil organic matter are used in the design of measures to form a deficient balance of humus. Information on the availability of arable soils with mobile forms of phosphorus and potassium is necessary for calculating doses of mineral fertilizers. With low availability of mobile forms of sulphur and trace elements, recommendations are being developed for the use of fertilizers containing scarce elements. As a result of the implementation by agricultural producers of projects of adaptive landscape systems of agriculture and soil protection, in 2015-2018, compared to 2010-2014, the use of mineral fertilizers increased by 14.4 kg/ha, organic - by 3.3 tons/ha, lime production - by 38.1 thousand ha/year. As a result, arable land productivity increased by 1.01 thousand feed units