A tunable comb filter based on a fiber loop mirror setup, which incorporates a piece of pumped erbium-ytterbium co-doped polarization maintaining fiber, is newly presented. It is accomplished by controlling the pump power or adjusting a polarization controller in the loop mirror, which results from the fact that the effective birefringence of the erbium-ytterbium co-doped polarization maintaini...

Single-frequency laser operation near 2 microm has been demonstrated in an all-fiber short-cavity (2-6 cm) distributed feedback laser cavity using both cladding- and core-pump configurations in a newly developed heavily Tm-doped multicomponent silicate glass fiber. Using a single-mode Er-doped fiber laser at 1575 nm as a core-pump source, a 2-cm-long distributed Bragg reflector fiber laser deli...

Surface damage is one of the most problematic power limits in high-power fiber laser systems. All-fiber Faraday components are demonstrated as a solution to this problem, since they can be completely fusion-spliced into existing systems, eliminating all glass-air interfaces. Beam filamentation due to self-focusing places another limit on the peak power attainable from fiber laser systems. The l...

The effects of long-term (over several years) anabolic androgen steroids (AAS) administration on human skeletal muscle are still unclear. In this study, seventeen strength training athletes were recruited and individually interviewed regarding self-administration of banned substances. Ten subjects admitted having taken AAS or AAS derivatives for the past 5 to 15 years (Doped) and the dosage and...

We report a peak gain of 1.2dB/cm at 1535nm in an Erbium:Lutecium codoped Al/P/Si fibre fabricated using a standard MCVD and solution doping technique. This is the highest gain per unit length yet reported in an Erbium doped fiber amplifier. The incorporation of Lutetium into the glass is shown to reduce the erbium ion clustering within the fiber. The highest gain per unit length yet reported f...

The field of optics has a drastic impact in the field of electronics and communication. With the rising need for higher data transfer rate, optical advancements have served this purpose. Optical amplifiers play a crucial role in the amplification of signal at regular intervals to avoid loss of data. Erbium doped fiber amplifiers (Erbium Doped Fiber Amplifier) carry out the amplification by stim...

The composite cavity fiber laser (CCFL) is relatively simple in its fabrication, as it is essentially three wavelength matched Bragg gratings in a section of doped fiber. By using internal feedback with unequal sub-cavity lengths, unidirectional CCFLs with significantly asymmetric output power from its two outputs can be achieved. Preliminary results also show that it is possible for the lasing...

We present pulsed laser operation in a Nd-doped, Y3Al5O12-based silica fiber. The fiber was fabricated using the rod-in-tube technique with a Nd:YAG crystal rod as the core material and a silica tube for the cladding material. A spectroscopy study revealed that the core region had become amorphous in the process of fiber drawing. Q-switched pulsed laser operation was realized at a wavelength of...

We present the results of the experimental study and comparison of Yb-free, Erdoped, all-fiber, alignment free, single frequency (SF) fiber amplifiers operating under 980-, 1470and 1530-nm pumping for the coreand clad-pumping architectures. In the single-mode core-pumped configuration Er-doped fiber amplifiers demonstrated 52% and 60% pump to output efficiencies for 980 and 1480 nm pump wavelen...

We report the demonstration of the first, to our knowledge, cladding-pumped continuous-wave Yb(3+)-doped phosphate-glass fiber laser. Phosphate hosts are of interest because they can be much more heavily doped than silica, and because of the possibility that they may have a higher photodarkening threshold. In an 84.6 cm double-clad fiber doped with 12 wt. % of Yb(2)O(3) and laser-diode pumped a...