Distributed bragg reflector , amplified

Distributed Bragg reflector (DBR) and distributed feedback (DFB) fiber lasers have relatively short cavities, e.g., 10 cm or less, facilitated by the use of heavily doped-fiber amplifiers. The aim is to provide increased cavity mode... 

Although many diode lasers work as multimode lasers, the distributed feedback (DFB) and distributed Bragg reflector (DBR) lasers show a mode selection because of their periodic structure. The mode selectivity is generated by the optical properties of the periodic stmctures because (Mily the modes that are associated with a standing wave/stop band are amplified. DFB structures are photonic structures, which are doped throughout the volume with chromophores (in an optimal case at the maxima of the standing waves), whereas DBR lasers have a miniature Fabry-Perot cavity in which the dye is localized, and the mirrors are replaced by periodic gratings [85]. 

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