The route toward a diode-pumped 1-W erbium 3-/spl mu/m fiber laser

Abstract

Index Terms-Diode-pumped lasers, infrared lasers, laser biomedical applications, optical fiber lasers, rare earth lasers.

Laser-tissue interaction with a continuous wave 3-?m fibre laser: Preliminary studies with soft tissue

“…Samples were mounted on an x-y-z translation stage and irradiated in air. A single 35-mm focal length CaF 2 lens was used to focus the laser output onto the tissue surface, providing an incident spot size of approximately 150 m. Green fluorescence light produced by upconversion and excited-state absorption (ESA) processes in the fibre core [9] assisted in alignment and the laser power was regularly monitored with a Coherent 210 power meter.…”

Analysis of heat generation and thermal lensing in erbium 3-μm lasers

“…Nevertheless, significant heat is also generated in this system. The lifetime-quenching regime [36] that is achieved by co-doping the fiber with Pr ions has so far produced the highest reported output power of 1.7 W from a fiber laser at 3 m [37]. The MPR that occurs within Pr after energy transfer from the lower laser level of Er generates an amount of heat, which is of the absorbed 975-nm pump power in the ideal case and may further increase if parasitic processes come in.…”

Simple and efficient method of lines based algorithm for modeling of erbium doped Q-switched fluoride fiber lasers

“…Due to the presence of strong oscillations during the switch on process [12] ODE integration schemes suitable for stiff systems need to be applied.…”

“…The design of fluoride glass based erbium doped fiber lasers has therefore attracted significant attention. Several models were developed for modelling erbium doped fluoride fiber lasers and amplifiers [9][10][11][12][13][14]. These laser models rely on solving the rate equations and the propagation equations for the pump and signal waves in the time domain and are closely related to models used for time domain simulations of Q-switched silica glass based fiber lasers [15] and Raman fiber amplifiers [16].…”

“…These laser models rely on solving the rate equations and the propagation equations for the pump and signal waves in the time domain and are closely related to models used for time domain simulations of Q-switched silica glass based fiber lasers [15] and Raman fiber amplifiers [16]. In [9][10][11][12][13][14] the partial differential equations (PDEs) that describe the propagation of forward and backward travelling waves for the pump and signal in these models were reduced to a set of ordinary differential equations (ODEs) using the method of characteristics (MOC). However, for MOC the spatial and temporal step ratio is fixed and has to be kept at a constant value equal to the optical wave group velocity for the transient results to preserve their physical meaning.…”