We show a quantitative connection between Refractive Index Profiles (RIP) and measurements made by an Atomic Force Microscope (AFM). Germanium doped fibers were chemically etched in hydrofluoric acid solution (HF) and the wet etching characteristics of germanium were studied using an AFM. The AFM profiles were compared to both a concentration profile of the preform determined using a Scanning E...

This paper describes the design and implementation of an advanced photonics experiment aimed at the undergraduate students’ level. The experiment uses erbium-doped fiber to implement three functions through slight modifications of the setup. The functions are a broadband light source, a multi-wavelength optical amplifier, and a tunable fiber laser. As part of an Optical Communication Systems co...

Ytterbium (Yb) doped fiber lasers are known to be affected by the creation of color centers during lasing (socalled photodarkening (PD)). In a previous work, this defect creation was investigated from a spectroscopic point of view, showing the presence of traces (ppb) of thulium (Tm) in the Yb doped fiber. It was shown that Tm has a strong impact on the defect creation process involved in PD. I...

Erbium-doped fiber is a gain medium exhibiting homogeneous line broadening at room temperature, while a semiconductor optical amplifier has a dominant feature of inhomogeneous line broadening. In this work, a semiconductor optical amplifier is incorporated into the cavity of an erbium-doped fiber ring laser to form a hybrid gain medium. Theoretical analysis shows that such a gain medium support...

We adopt a three-level scheme for the pump – amplification process in 1.48 m pumped Erbium-Doped Fiber Amplifiers, which reproduces the main experimental features of amplifiers with short and long fiber lengths. Continuous wave amplification in a simplified slab waveguide structure is simulated by means of the scalar Beam Propagation Method, taking into account signal and pump propagation throu...

We propose and demonstrate a stable, tunable and narrow linewidth C-band lanthanum co-doped bismuth based erbium doped fiber (EDF) ring laser with single longitudinal mode (SLM) operation. A free space thin film filter acts as a wavelength discriminative component selecting a few oscillating modes while a Lyot filter formed by a polarization maintaining (PM) fiber and a linear polarizer further...

We present, to the best of our knowledge, the first demonstration of a 2 μm Brillouin laser based on a thulium-doped fiber pump and a chalcogenide fiber. A short 1.5 m piece of suspended-core chalcogenide As38Se62 fiber is employed as a gain medium, taking advantage of its small effective mode area and high Brillouin gain coefficient. A record-low lasing threshold of 52 mW is achieved, which is...

The concept of an effective Verdet constant is proposed and experimentally validated. The effective Verdet constant of light propagation in a fiber includes contributions from the materials in both the core and the cladding. It is measured in a 25 wt.% terbium-doped-core phosphate fiber to be -6.2+/-0.4 rad/(Tm) at 1,053 nm, which is six times larger than silica fiber. The result agrees well wi...

An Er"+-doped fiber ring laser with unidirectional operation without optical isolator has been investigated for different cavity conditions. The fiber ring laser cavity is built in such a way that the optical fields propagating in the two directions suffer different losses. As a consequence, the laser oscillation appears in a quasi-unidirectional form. By incorporating a fiber pigtailed bandpas...

We report on two types of polarization maintaining solid photonic crystal fibers that guide light by a combination of a photonic bandgap and total internal reflection. Group and phase birefringence are studied experimentally and numerically for stress-applying parts made from B-doped and F-doped silica. The stress field originating from Ge-doped cladding rods is shown to interfere with the stre...