RESUMEN
We experimentally demonstrate the generation of 1.024-Tb/s Nyquist-WDM phase-conjugated vector twin waves (PCTWs), consisting of eight 128-Gb/s polarization-division-multiplexed QPSK signals and their idlers, by a broadband polarization-insensitive fiber optic parametric amplifier. This novel all-optical signal processing approach to generate WDM-PCTWs enables a 2-fold reduction in the needed optical transmitters as compared to the conventional approach where each idler is generated by a dedicated transmitter. Digital coherent superposition of the twin waves at the receiver enables more than doubled reach in a dispersion-managed transmission link. We further study the impact of polarization-mode dispersion on the performance gain brought by the phase-conjugated twin waves, showing a gain of ~3.8 dB in signal quality factors.
RESUMEN
Experimental demonstration of an all-fiber, all-optical continuously tunable delay line is reported. The 1.56-micros delay with a record 62,400 time-delay bit-rate product was characterized for a 40-Gbps data channel. The result was enabled by parametric dispersion compensation with cascaded triple-conversion in highly-nonlinear fiber capable of continuous tuning over 39.5 nm.
RESUMEN
We measure impairment of on-off-keyed and differential-phase-shift-keyed signals imposed by gain saturation in a fiber parametric amplifier. Phase modulation is observed to be more robust, particularly for deep (15 dB) saturation.
RESUMEN
We experimentally examine the noise properties of a two-pump optical parametric amplifier when converting frequencies using the Bragg-scattering (BS) and phase-conjugation (PC) processes. Using co-polarized pumps and signal, we show that the noise performance is limited by spontaneous Raman scattering. The noise performance of BS is superior to that of PC, and should improve with larger frequency excursions.
RESUMEN
We show theoretically that the gain spectrum obtained by cascading two or more semiconductor optical amplifiers can have a ripple amplitude that is significantly smaller than that currently attainable with a single stage of optical amplification. For example, by cascading two stagger-tuned amplifiers, each having 10 dB of coupling loss and facet reflectivities of 10(-3), one can achieve a net (fiber-to-fiber) gain of 30 dB with less than 2 dB of ripple amplitude. We also show that, under some conditions, simple cascading of optical amplifiers, without the stagger tuning and associated control, can lead to low-ripple, high-gain optical amplification.
RESUMEN
A Jones matrix is constructed for a fiber that exhibits first- and second-order polarization mode dispersion (PMD). It permits the modeling of pulse transmission for fibers whose PMD vectors have been measured or whose statistics have been determined by established PMD theory. The central portion of our model is a correction to the Bruyère model.
RESUMEN
Extreme ultraviolet (XUV) radiation from 100 to less than 30 nm is emitted from a laser-induced plasma generated on a liquid-mercury surface. This surface does not degrade even after tens of thousands of laser pulses. The 532-nm laser light focused on the mercury forms a bright plasma core and a plume extending several millimeters above the liquid level. The plasma core produces primarily continuum radiation, whereas the plume emits lines at wavelengths above 77 nm. The mercury plasma was generated at the entrance port of a normal incidence vacuum monochromator, and the dispersed XUV radiation was monitored with a photomultiplier tube.