Recent Progress in the Development of Neodymium-Doped Ceramic Yttria

Abstract

Solid-state lasers play a significant role in providing the technology necessary for active remote sensing of the atmosphere. Neodymium doped yttria (Nd:Y 2 O 3 ) is considered to be an attractive material due to its possible lasing wavelengths of ~914 nm and ~946 nm for ozone profiling. These wavelengths when frequency tripled can generate UV light at ~305 nm and ~315 nm, which is particularly useful for ozone sensing using differential absorption lidar technique. For practical realization of space based UV transmitter technology, ceramic Nd:Y 2 O 3 material is considered to possess great potential. A plasma melting and quenching method has been developed to produce Nd 3+ doped powders for consolidation into Nd:Y 2 O 3 ceramic laser materials. This far-from-equilibrium processing methodology allows higher levels of rare earth doping than can be achieved by equilibrium methods. The method comprises of two main steps: (a) plasma melting and quenching to generate dense, and homogeneous doped metastable powders, (b) pressure assisted consolidation of these powders by hot isostatic pressing to make dense nanocomposite ceramics. Using this process, several 1" x 1" ceramic cylinders have been produced. The infrared transmission of undoped Y 2 O 3 ceramics was as high as ~75% without anti-reflection coating. In the case of Nd:Y 2 O 3 ceramics infrared transmission values of ~50% were achieved. Furthermore, Nd:Y 2 O 3 samples with dopant concentrations of up to ~2 at. % were prepared without significant emission quenching.

Biolabeling with nanoparticles based on Y2O3: Nd3+ and luminescence detection in the near-infrared

“…The narrow absorption bands of the Nd 3 + ion were assigned to the 4 I 9/2 -2 G 7/2 + 2 G 5/2 (579 and 597 nm), 4 I 9/2 -2 H 11/2 (627 nm), 4 I 9/2 -4 F 9/2 (689 nm), 4 I 9/2 -4 F 7/ 2 + 4 S 3/2 (745 and 759 nm), 4 I 9/2 -4 F 5/2 + 2 H 9/2 (805 and 821 nm) and 4 I 9/2 -4 F 3/2 (893 nm) transitions [32]. Typical absorption transitions of the Y 2 O 3 :Nd 3 + nanopowder were observed with similar spectral profiles to the absorption recorded for samples prepared by the ceramic method [22,33]. The Nd 3 + ion has an odd-electron 4f 3 configuration; therefore it was labeled as a Kramer ion due to its electronic states, which are at least doubly degenerate for any crystal field perturbation.…”

“…Our proposal is to use this high intensity emission in the area of immunoassays on the basis of the reasons given above. In addition, the Y 2 O 3 matrix does not exhibit luminescence in the NIR region [22].…”

“…The Nd 3 + ion doped in a Y 2 O 3 matrix [22] used in immunoassays can be beneficial, since it absorbs in both the visible and infrared regions (500-900 nm) with subsequent emission in the NIR region. Energy level diagram of the Nd 3 + ion corresponding to absorbing levels may be excited using a laser pump at 808 nm, with emissions from the excited 4 F 3/2 state to 4 I 9/2 (890 nm), 4 I 11/2 (1060 nm) and 4 I 13/2 (1340 nm) manifolds.…”

Microstructuration induced differences in the thermo-optical and luminescence properties of Nd:YAG fine grain ceramics and crystals

“…As for example, the preparation procedure of Nd:YAG ceramics allows for the incorporation of high Nd 3+ doping levels without an appreciable reduction in their optical quality as well as to large gain media with the additional possibility of layered structure fabrication. [7][8][9] In addition, some previous works have pointed out the superior mechanical properties on Nd:YAG ceramics when compared to Nd:YAG crystals. 1 Finally, the actual composition of Nd:YAG is improved in ceramics with respect to crystals in which, depending on the growth procedure, a nonhomogeneous distribution of yttrium and aluminum can be induced ͑as it could be the case of the Nd:YAG crystals grown by the Czochralski technique͒.…”

Testing of laser components subjected to exposure in space

“…Figure 1 shows the optical items mounted on a specimen holder. The laser diode, diode bar, ceramic yttria 3 and Bismuth doped PbTe are visible. Other elements are below a secondary plate and are hidden from the direct view.…”