Core-clad Pr(3+)-doped Ga(In)-Ge-As-Se-(I) glass fibers: Preparation, investigation, simulation of laser characteristics

Abstract

a b s t r a c t sСore-clad  bers on the basis of high-purity 1300 ppmw Pr(3+ )-doped Ga-Ge-As-Se and 2000 ppmw Pr(3+ )-doped In-Ge-As-Se-I glasses have been prepared. The minimum optical losses of the  bers are at the level of 1 dB/m in the w avelength range, w here there is no in uence of the praseodym ium absorption. At present, it is the best result obtained for core-clad rare-earth-doped chalcogenide  bers w ith high dopant concentration. The  bers exhibit the broadband luminescence in the spect ral range of 3.5 -5.5 m. The values of luminescence lifetime at the w avelength of 4.7 m are w ithin 6.5-8.2 ms closed to those for the bulk glasses obtained previously. Simulation of laser properties for these core-clad  bers in the three-level cascade scheme w as carried out. The low level of optical losses experimentally achieved in these  bers is one of main criteria for development of mid-IR  ber systems. Int r oduct i onChalcogenide glasses (ChG) doped w ith rare earth elements (REE) are w idely discussed in the scienti c literature regarding the possibility of their using for creation of middle infrared (mid-IR)  ber lasers and ampli ers. At present, laser  ber materials for the spectral region beyond 3.9 m have not been experimentally developed. So, ChGs are of current interest due to their characteristics, such as low phonon energies (dow n to 350 cm -1 ), high transparency in the mid-IR range, potential ultra low optical losses, an ability to dissolve the rare earth elements, as w ell as the high calculated values of the quantum ef ciency and lasing slope ef ciency. To characterize the laser  ber materials, the quantum ef ciency determined as a ratio betw een experimental and calculated values of emission lifetime, the lasing slope ef ciency, and the threshold pow er are used to be considered. These characteristics have been evaluated by numerical simulations for the number of chalcogenide multi-component glasses doped w ith REE, taking into consideration the different pump parameters [1][2][3][4][5][6]. Data show ed the high values of quantum ef ciency (up to 100%) and the lasing slope ef- ciency (up to 54%) of these glasses for the mid-IR range.The main advantages of selenide chalcogenide glasses, as potential laser media, are low phonon energy values (230-300 cm -1 ), the possibility to incorporate the rare earth elements in relatively high concentration (thousands of ppm), high values of refractive index (2.6-2.9, depending on glass composition), and, as a consequence, the high values of absorption cross section at the pump w avelength. The set of these properties of ChGs had predetermined a choice of research subjects here, namely, Pr(3+ )-doped Ga(In)-Ge-As-Se glasses and  bers as the materials promising for mid IR-range.Due to the need to prepare  ber laser materials w ith low optical losses, the main focus had been done on the development of ChGs w ith a low content of limiting impurities w hich have negative in- uence on the spectral characteristics of glasses in the range of ...

Comparative Modeling of Infrared Fiber Lasers

“…It is noted that the value of 1 dB/m for chalcogenide fiber loss at 4600 nm was challenging in practical realization. However, a low value of the fiber loss is necessary for the realization of an efficient fiber laser and is thus widely used in fiber laser modeling-related literature [17,25,[42][43][44].…”

Experimental and numerical investigation to rationalize both near-infrared and mid-infrared spontaneous emission in Pr3+ doped selenide-chalcogenide fiber

“…These characteristics make chalcogenide glasses a promising host material for rare-earth ions [6][7][8][9][10]. Recent publications show that there is a particularly large interest in the mid-infrared photoluminescence from Pr 3+ doped low phonon materials [11][12][13][14][15][16][17]. This is because a Pr 3+ ion dopant in a chalcogenide glass has a high pump absorption cross-section [18], and also because it can be pumped with commercially available laser diodes operating at 1.55 µm and 1.94 µm.…”

Experimental observation of gain in a resonantly pumped Pr3+-doped chalcogenide glass mid-infrared fibre amplifier notwithstanding the signal excited-state absorption

“…Among them, Pr 3+ -doped chalcogenide glass fibre has been fabricated into small-core step index fibre with optical fibre loss around 2 dB/m, which can be applied practically towards a MIR laser 22,23 . The transition of the Pr 3+ ion from the first excited-state 3 H 5 to the ground-state 3 H 4 presents a broad emission cross-section from 4 to 6 μm, and the absorption cross-section within these two states is from 3.5 to 5.5 μm 24,25 .…”