High-power, Joule-class, temporally shaped multi-pass ring laser amplifier with two Nd:glass laser heads

Abstract

A high-power, Joule-class, nanosecond temporally shaped multi-pass ring laser amplifier system with two neodymium-doped phosphate glass (Nd:glass) laser heads is demonstrated. The laser amplifier system consists of three parts: an all-fiber structure seeder, a diode-pumped Nd:glass regenerative amplifier and a multi-pass ring amplifier, where the thermally induced depolarization of two laser heads is studied experimentally and theoretically. Following the injection of a square pulse with the pulse energy of 0.9 mJ and pulse width of 6 ns, a 0.969-J high-energy laser pulse at 1 Hz was generated, which had the ability to change the waveform arbitrarily, based on the all-fiber structure front end. The experimental results show that the proposed laser system is promising to be adopted in the preamplifier of high-power laser facilities.

The fabrication of nanodiamond doped tellurite germanate glass with robust structure and its luminescence

“…Obviously, the 88.46% area percentage of TeO 4 tbp is higher than 11.54% of TeO 3 tp. Conclusively, both TeO 4 and TeO 3 units consist in tND‐TZNGB glass but the TeO 4 amount is predominant in the amorphous structure, which is in agreement with previous XPS studies of alkali tellurite glasses 44,52,53 . The alkali metal oxide Na 2 O converts TeO 4 tbp to TeO 3 tbp by disrupting the Te‐O‐Te bonds in the network structure, which affects the coherence and thermal stability of the network structure.…”

“…Despite the shape of the bands is not changed by bits of GeO 2 and B 2 O 3 addition, slight shifts of band positions happen in TZNGB glass. The blue shift of Te‐O‐Te stretching vibration is due to the deformation of Te‐O‐Te bond caused by the introduction of GeO 2 42–44 . The blue shift at near 678 cm ‐1 might be attributed to the formation of [GeO 4 ] 4‐ units after the addition of GeO 2 , which can provide partial oxygen ions to achieve the network continuity and relative stability in a tellurite glass structure 45–47 …”

“…The blue shift of Te-O-Te stretching vibration is due to the deformation of Te-O-Te bond caused by the introduction of GeO 2 . [42][43][44] The blue shift at near 678 cm -1 might be attributed to the formation of [GeO 4 ] 4units after the addition of GeO 2 , which can provide partial oxygen ions to achieve the network continuity and relative stability in a tellurite glass structure. [45][46][47] Raman and PL measurement of t-ND that have been treated by annealing and oxidation and raw ND powder were performed, as shown in Figures 4 and 5, respectively.…”

“…Conclusively, both TeO 4 and TeO 3 units consist in tND-TZNGB glass but the TeO 4 amount is predominant in the amorphous structure, which is in agreement with previous XPS studies of alkali tellurite glasses. 44,52,53 The alkali metal oxide Na 2 O converts TeO 4 tbp to TeO 3 tbp by disrupting the Te-O-Te bonds in the network structure, which affects the coherence and thermal stability of the network structure. The incorporation of cations with charge greater than 1, such as B 3+ and Ge 4+ , leads connection of lone pair electrons on tbp and tp, which enhances the continuity of the network structure and improves the thermal stability.…”

Visible emission and energy transfer in Tb3+/Dy3+ co‐doped phosphate glasses

“…Among oxide glasses, phosphate glasses are known for high transparency, high solubility of rare‐earth ions, low photo‐darkening, and mature manufacturing technology 19‐21 . Although in principle phosphate glasses allow a much higher doping concentration of Tb 3+ , multiphoton absorption 9 counterbalances the benefits of increased dopant concentration in practice.…”