Random lasing in a short Er-doped artificial Rayleigh fiber

Observation of direction instability in a fiber ring laser

“…A major one relies on the disordered Rayleigh scattering in a kilometer-long telecom fiber in combination with stimulated Raman scattering to create the necessary feedback for lasing 14 , 15 . Another one relies on population inversion dynamical gratings in a cavity that is mainly constituted of the active fiber only 16 , 17 . Both mechanisms might have a relation to the phenomenon presented here, as will be discussed later.…”

Photosensitive Yb-Doped Germanophosphosilicate Artificial Rayleigh Fibers as a Base of Random Lasers

“…In fact, random fiber lasers are able to produce light with unique performance characteristics without imposing stringent requirements on the cavity configuration. Current trends in Fibers 2021, 9, 53 2 of 9 random fiber lasers are associated with evolution of long (10-100 km) cavities based on SMF-28 fibers to short laser configurations based on short (~10m) FBG array fibers referred to as artificial Rayleigh fibers [8,9]. The use of artificial Rayleigh fibers, as the cavity of a random laser not only reduces the cavity length to acceptable values, but also provides the spectral selection of lasing generation at the reflection wavelength of the FBG array.…”

“…In the latter case, a promising direction is the inscription of the FBG arrays in an optical fiber-doped with rare-earth elements such as erbium, ytterbium, etc. This provides greater spectral and signal level stabilization of laser radiation because the dynamic gratings forming exactly in the laser's cavity [9,10].…”

“…However, it should be noted that the optical fiber chosen for inscribing FBGs during the drawing process should have a sufficient initial photosensitivity [8]. In [9], the possibility of fabricating a laser cavity from an array of FBGs inscribed in a segment of the Er-doped fiber with a relatively low concentration of Er 3+ ions (Er absorption~20 dB/m at a wavelength of 1530 nm) was demonstrated. The developed laser stably generated single-frequency radiation at a wavelength of 1547.6 nm with a narrow line (width less than 1 kHz).…”

Искусственные Рэлеевские Волокна И Их Применение В Лазерах

“…Запись массивов ВБР также возможно производить во время вытяжки ОВ легированного ионами эрбия [11][12]. Это позволяет создать ОВ, совмещающие в себе как повышенную отражательную способность, так и возможность формирования динамических решёток, которые крайне важны для спектральной селекции лазерного излучения.…”