Laser ions erbium

Johnson et al. (55) observed energy transfer from erbium to thulium and from erbium to holmium ions in crystals. They were able to obtain substantial decreases in laser thresholds because of this energy migration. The fluorescent lifetime of the 3//4 state of thulium in CaMo04 containing 0.75 atomic per cent erbium and 0.5 atomic per cent thulium as inferred from the time delay before the onset of laser oscillation is 900 /xsec at both IT and 20°K. 

Rg. 12. Erbium-doped light amplifier. Light from a diode laser pump excites erbium ioas in segment of an optical fiber. These ions then emit light and thus boost a passing optical signal. (After AT T Bell Laboratories)... 

The commercially important samarium-containing minerals are treated with concentrated sulfuric acid or, in the case of monazite, with a solution of sodium hydroxide (73%) at approximately 40°C (104°E) and under pressure. The element is separated from the solutions via solvent extraction or ion exchange. Sm salts are weakly yellow and may exhibit ion emission. Sm ions show luminescence and are sometimes used to generate lasers. Samarium is used in the manufacture of headphones and tape drivers, see ALSO Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Lutetium Neodymium Praseodymium Promethium Terbium Ytterbium. 

Rare earth ions have been paid much attention to for their partieular optical properties and magnetic properties. Rare earth compound have been widely used as laser materials, lumineseent materials, coloring agents of ceramics or glass and so on l The optical materials doped erbium ion have been widely investigated for this ion has abundant energy levels. The energy levels and... 

S3/2— I15/2) of erbium ion have a laige emission section and are easy to achieve upconversion, so erbium ion is a good active ion as upconversion phosphors materials. The energy level transition( l]3/2— I15/2) can emit out 1.5 pm eye-safe laser radiation and the ion is also a well active ion for the eye-safe laser material. Gd203 powder with a cubic structure is a good host material for its excellent photics and thermal properties. It not only can be used as upconversion phosphors material but also can be used to prepare transparent ceramics as a host material. 

Feuchter T., Mwarania E.K., Wang J., Reekie E., Wilkinson J.S., Erbium-doped ion-exchanged waveguide lasers in BK-7 glass, IEEE Photon. Technol. Lett. 4 (6), 542-544... 

Despite all the technological applications and investigations of rare-earth YAG lasers, the optical spectra of some of the rare-earth ions in this host are of questionable quality and in some cases nonexistent. Only two rare-earth ions in YAG, neodymium and erbium, have been thoroughly investigated and reported. This is rather surprising when compared to lanthanum trifluoride (LaFa), for which Kaminskii reports only 16 lasers, although abundant excellent data exist (Camall et al., 1977) for all of the rare-earth ions in LaFs except terbium. 

Specific examples of semiconductor laser array pumps include devices made from the AlGaAs material system. The emission wavelength can be varied from 700 to 900 nm by varying the Ga/Al composition. These emission wavelengths can be made to coincide with absorption bands of several important solid state lasing ions, such as neodymium, chromium, holmium, erbium, and promithium. 

F ure 17-10. Sketch of the setup used to measure optical properties of a sol-gel waveguide doped with erbium/ytterbium ions. Different pigtailed laser diodes and dfferent output coupling configurations may be mixed, in order to perform specific measurements. 

Light amplifiers are essential to all-optical systems (no electronic repeaters, no hght-to-electronic conversion) since they compensate for optical losses within the fibers and the associated connectors, couplers, and switches. They are achieved by doping the fiber core with fluorescent lasing ions such as erbium or neodymium, and pumping using laser diodes. 

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