W. Luthy

Diode pumped 2.79 /spl mu/m Er/sup 3+/:Cr/sup 3+/:YSGG laser

In this paper, we report on lasing at 2.79 /spl mu/m under 974 nm diode laser excitation in an Er:YSGG crystal codoped with chromium. The host is YSGG, an Y/sub 3/Sc/sub 2/Ga/sub 3/O/sub 12/ crystal. The present Cr/sup 3+/:Er/sup 3+/:YSGG crystal is grown by the Czochralski method at the Institute of General Physics in Moscow. The crystal has a thickness of 3 mm and its absorption coefficient at 974 nm is 2.6cm/sup -1/. Therefore, 54.2% of the incident pump power is absorbed in the crystal. The 2.79 /spl mu/m radiation occurs from the transition of /sup 4/I/sub 11/2/ to /sup 4/I/sub 13/2/ in Er/sup 3+/. The best absorption of the Er/sup 3+/ ions is at 976 nm. The laser threshold is about 0.5 W and increases with a rising pump wavelength. The slope efficiency is 3.4 %. The resonator configuration is by no means optimized.

Diode pumped 2.79 μm Er/sup 3+/:Cr/sup 3+/:YSGG laser

In this paper, we report on lasing at 2.79 /spl mu/m under 974 nm diode laser excitation in an Er:YSGG crystal codoped with chromium. The host is YSGG, an Y/sub 3/Sc/sub 2/Ga/sub 3/O/sub 12/ crystal. The present Cr/sup 3+/:Er/sup 3+/:YSGG crystal is grown by the Czochralski method at the Institute of General Physics in Moscow. The crystal has a thickness of 3 mm and its absorption coefficient at 974 nm is 2.6cm/sup -1/. Therefore, 54.2% of the incident pump power is absorbed in the crystal. The 2.79 /spl mu/m radiation occurs from the transition of /sup 4/I/sub 11/2/ to /sup 4/I/sub 13/2/ in Er/sup 3+/. The best absorption of the Er/sup 3+/ ions is at 976 nm. The laser threshold is about 0.5 W and increases with a rising pump wavelength. The slope efficiency is 3.4 %. The resonator configuration is by no means optimized.

Diode pumped 2.79 μm Er 3+ :Cr 3+ :YSGG laser

In this paper, we report on lasing at 2.79 /spl mu/m under 974 nm diode laser excitation in an Er:YSGG crystal codoped with chromium. The host is YSGG, an Y/sub 3/Sc/sub 2/Ga/sub 3/O/sub 12/ crystal. The present Cr/sup 3+/:Er/sup 3+/:YSGG crystal is grown by the Czochralski method at the Institute of General Physics in Moscow. The crystal has a thickness of 3 mm and its absorption coefficient at 974 nm is 2.6cm/sup -1/. Therefore, 54.2% of the incident pump power is absorbed in the crystal. The 2.79 /spl mu/m radiation occurs from the transition of /sup 4/I/sub 11/2/ to /sup 4/I/sub 13/2/ in Er/sup 3+/. The best absorption of the Er/sup 3+/ ions is at 976 nm. The laser threshold is about 0.5 W and increases with a rising pump wavelength. The slope efficiency is 3.4 %. The resonator configuration is by no means optimized.

Excitation of the thulium /sup 1/G/sub 4/ level

Summary form only given. Infrared pumped upconversion lasers in the visible wavelengths range are of great interest. We have found an excitation scheme for diode pumping laser action has not yet been reached but we have measured spectral properties of crystal and glass samples with various thulium concentration in the range from 300 nm to 2300 nm. Ytterbium is needed sensitise the excited state absorption and to enable efficient diode pumping at 940 nm or 790 nm. Lifetimes of the /sup 1/G/sub 4/ level of thulium are presented for several host materials.

Microchip laser based on an Nd{sup 3+}:GdVO{sub 4} crystal

A diode-pumped microchip laser based on an Nd3+:GdVO4 crystal was investigated. A maximum output power of about 4 W with a differential efficiency of 22% was obtained.A diode-pumped microchip laser based on an Nd{sup 3+}:GdVO{sub 4} crystal was investigated. A maximum output power of about 4 W with a differential efficiency of 22% was obtained. (lasers)

Excited-State Absorption in ZBLAN:Er/sup 3+/: Implications for a Diode-Pumped 3-/spl mu/m Fiber Laser

Effective excited-state absorption (ESA) cross-sections are measured in ZBLAN:Er3+ at 780-840 nm. Pump losses by ESA are present over the whole absorption band. Diode pumping at 979 nm seems more favorable for high-power 3-µm fiber lasers.