Fiber amplification of pulse bursts up to 20 mu J pulse energy at 1 kHz repetition rate

Cataloged from PDF version of article.We demonstrate burst-mode operation of a polarization-maintaining Yb-doped fiber amplifier. Groups of pulses with a temporal spacing of 10 ns and 1 kHz overall repetition rate are amplified to an average pulse energy of similar to 20 mu J and total burst energy of 0.25 mJ. The pulses are externally compressed to similar to 400 fs. The amplifier is synchronously pulsed-pumped to minimize amplified spontaneous emission between the bursts. We characterize the influence of pump pulse duration, pump-to-signal delay, and signal burst length. (C) 2011 Optical Society of Americ

Ansatz from Non-Linear Optics Applied to Trapped Bose-Einstein Condensates

A simple analytical ansatz, which has been used to describe the intensity profile of the similariton laser (a laser with self-similar propagation of ultrashort pulses), is used as a variational wave function to solve the Gross-Pitaevskii equation for a wide range of interaction parameters. The variational form interpolates between the noninteracting density profile and the strongly interacting Thomas-Fermi profile smoothly. The simple form of the ansatz is modified for both cylindrically symmetric and completely anisotropic harmonic traps. The resulting ground-state density profile and energy are in very good agreement with both the analytical solutions in the limiting cases of interaction and the numerical solutions in the intermediate regime.Comment: 4 pages, 3 figures, published versio

Diffraction-limited, 10-W, 5-ns, 100-kHz, all fiber laser at 1.55 um

Cataloged from PDF version of article.This Letter reports on an all-fiber-integrated master-oscillator, power amplifier system at 1.55 mu m producing 5-ns, 100-mu J pulses. These pulses are generated at a 100 kHz repetition rate, corresponding to 10 W of average power. The seed source is a low-power, current-modulated, single-frequency, distributed feedback semiconductor laser. System output is obtained from a standard single-mode fiber (Corning SMF-28). Consequently, the beam is truly diffraction limited, which was independently proven by M-2 measurements. Further increase of peak power is limited by onset of significant spectral broadening due to nonlinear effects, primarily four-wave mixing. Numerical simulations based on six-level rate equations with full position-and time-dependence were developed to model propagation of pulses through the amplifier chain. This capability allows minimization of the amplified spontaneous emission, which can be directly measured using a fast acousto-optic modulator to gate the pulses. (C) 2014 Optical Society of Americ

Controlling Fast Chaos in Delay Dynamical Systems

We introduce a novel approach for controlling fast chaos in time-delay dynamical systems and use it to control a chaotic photonic device with a characteristic time scale of ~12 ns. Our approach is a prescription for how to implement existing chaos control algorithms in a way that exploits the system's inherent time-delay and allows control even in the presence of substantial control-loop latency (the finite time it takes signals to propagate through the components in the controller). This research paves the way for applications exploiting fast control of chaos, such as chaos-based communication schemes and stabilizing the behavior of ultrafast lasers.Comment: 4 pages, 4 figures, to be published in Physical Review Letter