Elias Snitzer

Pr3+-DOPED FLUORIDE FIBER AMPLIFIER OPERATING AT 1.31 µm

The authors propose a new Pr3+-doped fluoride fiber amplifier operating around 1.3 μm and demonstrate an effective amplification of 5.2 dB at 1.31 μm for the first time.

DOUBLE CLAD HIGH BRIGHTNESS Nd FIBER LASER PUMPED BY GaAlAs PHASED ARRAY

We report on the most recent improved version of the double clad configuration for efficient pumping of a single mode fiber laser with a multi-mode pump1 In the earlier report, the first and second claddings were substantially fused slica and the core containing Nd was offset from the center of the fiber axis, as shown in Fig. (1,a).

SiO 2 -clad fibers with selectively volatilized soft-glass cores

By using a thick-walled SiO(2) tube (25-mm outside diameter, 1-mm inside diameter), a soft-glass core containing Nd or Yb-Er has its alkali (and to a lesser extent its alkaline earth) components volatilized during drawing to give a good-quality laser fiber with Nd- or Yb-Er-doped cores.

Concentration effect on gain of Pr/sup 3+/-doped fluoride fiber for 1.3 mu m amplification

The concentration quenching mechanism in Pr/sup 3+/-doped fluoride fiber operating at the 1.3- mu m band is investigated. It is confirmed that the cooperative upconversion process causes signal gain saturation with pump power and degrades the gain characteristics of Pr/sup 3+/-doped fluoride fiber at a concentration of 1000 p.p.m. The reduction in gain coefficient due to cooperative upconversion is almost suppressed at a concentration of 500 p.p.m. A Pr/sup 3+/ concentration of 500 p.p.m. is a practical concentration for the fabrication of efficient Pr/sup 3+/-doped fluoride fiber amplifiers.<<ETX>>

Gain switching of a Nd +3 -doped fiber laser

We report the generation of gain-switched pulses near 1.06 microm from a Nd(+3)-doped single-mode fiber pumped at 590 nm. For a 5-cm-long fiber, pulses of 100 nsec at a 1-MHz repetition rate were obtained. For a 1-cm-long fiber, the pulse shortened to 40 nsec at repetition rates of up to 2.5 MHz for a single, independently drivable relaxation oscillation.

Rare earth fiber lasers

Abstract With the development of low-loss fibers and the availability of laser pump sources, there has been a renewed interest in rare earth doped glasses in fiber form. Of particular interest have been neodymium emitting at 1.06 and 1.33 μm and erbium at 1.55 μm. The last two wavelengths are in the wavelength windows now used in fiber-optic telecommunications. The interest in neodymium emitting at 1.06 μm is for the same reason as that in large neodymium glass systems, i.e. mainly for its efficient conversion of pump to laser light output. After a review of the early work on fiber lasers, the current activity with various rare earth fibers is described. The laser devices to be described are continuous wave oscillators, amplifiers, modelocked outputs, super-luminescent sources, and second-harmonic generators.

Gain characteristics of Pr/sup 3+/-Yb/sup 3+/ codoped fluoride fiber for 1.3 mu m amplification

The authors report on the ability of the Pr/sup 3+/-Yb/sup 3+/ codoped system to move the pumping wavelength to wavelengths shorter than 1.017 mu m. It was demonstrated that, by codoping of Yb/sup 3+/ with Pr/sup 3+/-doped fluoride fiber, amplifiers can be moved to the spectral range where effective pumping can be done with InGaAs laser diodes that have strained-layer quantum-well structures that were developed as a pumping source for Er/sup 3+/-doped fiber amplifiers. The pumping wavelength range was extended down to 0.93 mu m.<<ETX>>

Glass fiber laser at 1.36 μm from SiO 2 :Nd

By adding 14 mol % P{sub 2}O{sub 5} to the core of a SiO{sub 2}:Nd fiber, laser emission was obtained at 1.36 {mu}m. From the fluorescent spectra and laser thresholds for the {sup 4}{ital F}{sub 3/2} to {sup 4}{ital I}{sub 11/2} and {sup 4}{ital F}{sub 3/2} to {sup 4}{ital I}{sub 3/2} transitions, the net gain at 1.36 {mu}m is 0.024 dB/mW, and the ratio of excited-state absorption (the {sup 4}{ital F}{sub 3/2} to {sup 4}{ital G}{sub 1/2} transition) to stimulated emission is estimated to be 0.78.

Glass fiber laser at 1. 36. mu. m from SiO sub 2 :Nd

By adding 14 mol % P{sub 2}O{sub 5} to the core of a SiO{sub 2}:Nd fiber, laser emission was obtained at 1.36 {mu}m. From the fluorescent spectra and laser thresholds for the {sup 4}{ital F}{sub 3/2} to {sup 4}{ital I}{sub 11/2} and {sup 4}{ital F}{sub 3/2} to {sup 4}{ital I}{sub 3/2} transitions, the net gain at 1.36 {mu}m is 0.024 dB/mW, and the ratio of excited-state absorption (the {sup 4}{ital F}{sub 3/2} to {sup 4}{ital G}{sub 1/2} transition) to stimulated emission is estimated to be 0.78.

Glass fiber laser at 136 μm from SiO_2:Nd

By adding 14 mol % P{sub 2}O{sub 5} to the core of a SiO{sub 2}:Nd fiber, laser emission was obtained at 1.36 {mu}m. From the fluorescent spectra and laser thresholds for the {sup 4}{ital F}{sub 3/2} to {sup 4}{ital I}{sub 11/2} and {sup 4}{ital F}{sub 3/2} to {sup 4}{ital I}{sub 3/2} transitions, the net gain at 1.36 {mu}m is 0.024 dB/mW, and the ratio of excited-state absorption (the {sup 4}{ital F}{sub 3/2} to {sup 4}{ital G}{sub 1/2} transition) to stimulated emission is estimated to be 0.78.