Design of mid-IR microstructured fiber light source based on dysprosium doped chalcogenide glass
The paper deals with the design of a medium infrared (Mid-IR) light source based on a microstructured fiber made of dysprosium doped chalcogenide glass, Dy3+:Ga5Ge20Sb10S65. It is constituted by the cascade of a laser cavity and an optical amplifier which could be fabricated in the same microstructured fiber. In order to obtain realistic results, the simulation is performed by taking into account the spectroscopic parameters directly measured on preliminary samples of Dy3+:Ga5Ge20Sb10S65 glasses. The main objective is to investigate the feasibility of optical beam emission close to 4.4 μm wavelength. An output power of 547.3 mW with an input pump power of 3 W is calculated for an optical fiber about 1.5 m long and with a dopant concentration close to 6 × 1025 ions/m3. This result indicates that the designed source configuration is feasible for medium infrared light generation and it could find application in optical free propagation link, optical remote sensing and biomedicine.
Modelling of chalcogenide glass fibre lasers for MIR generation
The presentation gives an account of recent developments in the modelling of chalcogenide glass based lanthanide doped fibre lasers for the mid-infra-red (MIR) wavelength range. The particular lanthanide elements considered include dysprosium, praseodymium and terbium. Both classical 3 level lasing systems and cascade lasing systems are considered, and their properties compared. Steady state and pulsed operation of the lasers is considered and the possible application as a seed pump for supercontinuum generation is discussed. Several aspects of numerical methods used specifically for the modelling of MIR fibre lasers are also considered.
Microwave source with enhanced radiation power based on orbitron MASERs
We have proposed the design of high power microwave source in a vacuum tube based on the theory of negative mass instability. The proposed source does not operate based on a slow-wave structure but instead makes use of accelerated charged particles. In our structure, an electron emitter injects the charged particles into to the cavity. Emitted particles move around the anode, which leads to electron acceleration and emission of electromagnetic waves with a specific frequency. In this paper, we have enhanced the output power and frequency of microwave source by variation of particles initial energy and the number of anodes incorporating their specific arrangement and applied voltages. Working at room temperature, compactness, wide bandwidth, and tunability of output frequency are among the advantages of the proposed source.