Search results for "Toe"

Parabolic Pulse Amplifiers

2008

International audience; Recent studies in nonlinear optics have led to the discovery of a new class of ultrashort pulse generated in fiber amplifiers by the self-similar propagation of an arbitrary input pulse. These pulses with a parabolic shape and linear chirp, called `optical similaritons,' represent asymptotic solutions of the nonlinear Schrödinger equation with gain, towards which any initial pulse of given energy converges, independently of its intensity profile. Parabolic pulse amplifiers can be easily developed with standard optical fibers and commercial devices. Our goal here is to emphasize the main properties of similaritons and to discuss a few of their numerous new application…

Pulse quality analysis on soliton pulse compression and soliton self-frequency shift in a hollow-core photonic bandgap fiber.

2013

A numerical investigation of low-order soliton evolution in a proposed seven-cell hollow-core photonic bandgap fiber is reported. In the numerical simulation, we analyze the pulse quality evolution in soliton pulse compression and soliton self-frequency shift in three fiber structures with different cross-section sizes. In the simulation, we consider unchirped soliton pulses (of 400 fs) at the wavelength of 1060 nm. Our numerical results show that the seven-cell hollow-core photonic crystal fiber, with a cross-section size reduction of 2%, promotes the pulse quality on the soliton pulse compression and soliton self-frequency shift. For an input soliton pulse of order 3 (which corresponds to…

Tailored waveform generation in mode-locked fiber lasers by in-cavity pulse shaper

2014

International audience; We numerically show the possibility of pulse shaping in a mode-locked fiber laser by inclusion of an amplitude-phase spectral filter into the laser cavity. Various advanced temporal waveforms are generated, including parabolic, flat-top and triangular pulses.

Amplifier similariton fiber laser with nonlinear spectral compression

2012

International audience; We propose a new concept of a fiber laser architecture supporting self-similar pulse evolution in the amplifier and nonlinear spectral pulse compression in the passive fiber. The latter process allows for transform-limited picosecond pulse generation, and improves the laser's power efficiency by preventing strong spectral filtering from being highly dissipative. Aside from laser technology, the proposed scheme opens new possibilities for studying nonlinear dynamical processes. As an example, we demonstrate a clear period-doubling route to chaos in such nonlinear laser system.

Pulse shaping in mode-locked fiber lasers by in-cavity spectral filter

2014

International audience; We numerically show the possibility of pulse shaping in a passively mode-locked fiber laser by inclusion of a spectral filter into the laser cavity. Depending on the amplitude transfer function of the filter, we are able to achieve various regimes of advanced temporal waveform generation, including ones featuring bright and dark parabolic-, flat-top-, triangular- and saw-tooth-profiled pulses. The results demonstrate the strong potential of an in-cavity spectral pulse shaper for controlling the dynamics of mode-locked fiber lasers.

Effects of fourth-order fiber dispersion on ultrashort parabolic optical pulses in the normal dispersion regime

2011

International audience; We propose a new method for the generation of both triangular-shaped optical pulses and flat-top, coherent supercontinuum spectra using the effect of fourth-order dispersion on parabolic pulses in a passive, normally dispersive highly nonlinear fiber. The pulse re-shaping process is described qualitatively and is compared to numerical simulations.

Электрооптические свойства и особенности фазовых переходов в сегнетокерамиках цирконата-титана свинца, модифицированного лантаном и скандата-ниобата …

1978

Фоторефракция, аномальный фотовольтаический эффект и механизм электропроводности в сегнетокерамике цирконата-титаната свинца, модифицированного ланта…

1979

Advisor: Круминь, Андрис

Диэлектрические свойства сегнетоэлектрических твердых растворов со структурой перовскита в условиях высокого гидростатического давления

1980

Теория некоторых оптических свойств вибронных сегнетоэлектриков

1982

Advisor: Кристофель, Николай