Control of spectroscopic fluorescence parameters of Nd3+ ions as a function of concentration in a SiO2–Na2O–Al2O3–B2O3 glass system

AbstractExperimental evidence of spectroscopic parameter control was observed in Nd3+ ions embedded in a SiO2–Na2O–Al2O3–B2O3 glass system. The parameters Ω2,4,6 and others were determined by the Judd–Ofelt theory. It was found that these parameters were strongly dependent on Nd3+ concentration, indicating a ligand field change. This Letter will present and discuss possible mechanisms responsible for changes in the Judd–Ofelt parameters. Furthermore, non-radiative energy transfer mechanisms such as energy migration, cross relaxation and losses from networked phonons and OH− radicals, will be proposed to explain the observed decrease in 4F3/2→4I11/2 transition lifetime of Nd3+

Time Resolved Photoreflectance In Si:gaas Delta Doped Superlattices

In this paper we present a new Time Resolved Photoreflectance (TRPR) in δ-Si:GaAs superlattices. It is shown that PR spectra yield three contributions:(1) from intrinsic GaAs, (2) FKO due to the surface electric field and (3) FKO attributed to the buffer/superlattice interface. TRPR showed that the first contribution has the longest response time, while the second is faster and can be explained by a model proposed by Shen [1]. We interpret the faster characteristic decay times as the carriers recombination time of the first delta-doping plane and the surface states.274185188Shen, H., Dutta, M., Lux, R., Buchwald, W., Fotiadis, L., Sacks, R.N., (1991) Appl. Phys. Lett., 59, p. 321Aspnes, D.E., Studna, A.A., (1973) Phys. Rev, B7, p. 4605Shen, X.C., Shen, H., Parayanthal, P., Pollak, F.H., Schulman, J.N., Smirl, A.L., McFarlane, R.A., Haenens, I.D., (1986) Superlattices and Microstructures, 6, p. 513Ksendzov, A., Pollak, F., Amirtharaj, P.M., Wilson, J.A., (1988) J. of Gryst. Growth, 86, p. 586Shen, H., Hang, Z., Pan, S.H., Pollak, F.H., Woodall, J.M., (1988) Appl. Phys. Lett., 52, p. 2058Shen, H., Pollak, F.H., Woodall, J.M., Sacks, R.N., (1989) J. Vac. Sci. Techol., B7, p. 804Rhoderick, E.H., (1980) Metal-Semiconductor Contacts, p. 101. , Clarendon, OxfordDe Sousa, D.F., Bell, M.J.V., Nunes, L.A.O., to be publishedPires, M.P., Souza, P.L., Von Der Weid, J.P., (1994) Appl. Phys. Lett., 65, p. 88Shen, H., Dutta, M., (1995) J. Appl. Phys., 78, p. 2151Alperovich, V.L., Jaroshevich, A.S., Luubyshev, D.I., Migal, V.P., (1991) Physica B, 175, p. 15

Optical And Spectroscopic Properties Of Soda Lime Alumino-silicate Glasses Doped With Erbium And Silver

Spectroscopic properties of Ag/Er co-doped soda lime silicate glasses have been studied with the aim of assessing the effective role of silver as a sensitizer for erbium. Changes in spectroscopic properties of Er3+ as a function of silver addition to the base composition have been measured. Transmission electron microscopy (TEM), absorption as well as photoluminescence measurements in the visible and infrared spectral region, particularly 4I13/2 → 4I15/2 transition of the Er3+ ion were performed; excitation wavelengths in the range from 325 to 808 nm were used. Enhancement of the Er3+ luminescence at 1.54 μm was observed when Ag was added. © 2011 Elsevier B.V. All rights reserved.331219951998Pinchuk, A., Plessen, G.V., Kreibig, U., (2004) J. Phys. D: Appl. Phys., 37, pp. 3133-3139Guo, H., Wang, X.F., Chen, J.D., Li, F., (2010) Opt. Express, 18, pp. 18900-18905Pan, Z., Ueda, A., Aga, R., Burger, A., Mu, R., Morgan, S.H., (2010) J. Non-Cryst. Solids, 356, pp. 1097-1101Assumpcao, T.A.A., Da Silva, D.M., Kassab, L.R.P., De Araujo, C.B., (2009) J. Appl. Phys, 106, p. 063522Silva, D.M., Kassab, L.R.P., Luthi, S.R., Araujo, C.B., Gomes, A., Bell, M.J.V., (2007) Appl. Phys. Lett., 90, pp. 081913-081915Berneschi, S., Bettinelli, M., Brenci, M., Dall'Igna, R., Conti, G.N., Pelli, S., Profilo, B., Righini, G.C., (2006) Opt. Mater., 28, pp. 1271-1275Belharouak, I., Weill, F., Parent, C., Le Flem, G., Moine, B., (2001) J. Non-Cryst. Solids, 293-295, pp. 649-656Trukhin, A.N., (1995) J. Non-Cryst. Solids, 189, pp. 1-15Borsella, E., Cattaruzza, E., De Marchi, G., Gonella, F., Mattei, G., Mazzoldi, P., Quaranta, A., Polloni, R., (1999) J. Non-Cryst. Solids, 245, pp. 122-128Varma, R.S., Kothari, D.C., Tewari, R., (2009) J. Non-Cryst. Solids, 355, pp. 1246-1251Fedrigo, S., Harbich, W., Buttet, J., (1993) J. Chem. Phys., 99, pp. 5712-5717Felix, C., Sieber, C., Harbich, W., Buttet, J., Rabin, I., Schulze, W., Ertl, G., (1999) Chem. Phys. Lett., 313, pp. 105-109Paje, S.E., Garcia, M.A., Llopis, J., Villegas, M.A., (2003) J. Non-Cryst. Solids, 318, pp. 239-247Mattareli, M., Montagna, M., Vishnubhatla, K., Chasera, A., Ferrari, M., Righini, G.C., (2007) Phys. Rev. B, 75, p. 125102. , 1-7Sugimoto, S., Tanabe, J., (2005) Ceram. Soc. Jpn., 113, pp. 120-122Liao, M., Hu, L., Duan, Z., Zhang, L., Wen, L., (2007) Appl. Phys. B, 86, pp. 83-89Sheng, J., (2009) Int. J. Hydrogen Energy, 34, pp. 2471-2474Arnold, G.W., Borders, J.A., (1977) J. Appl. Phys., 48, pp. 1488-1496Marques, A.C., Almeida, R.M., (2007) J. Non-Cryst. Solids, 253, pp. 2613-261

Doped Tellurite Glasses: Extending Near-infrared Emission For Near 2.0 μm Amplifiers

Tm3+ singly doped and Tm3+/Ho3+-codoped TeO2-Bi2O3-ZnO-Li2O-Nb2O5 (TBZLN) tellurite glasses were successfully prepared by the melt-quenching technique. Emission characteristics and energy transfer mechanisms were studied upon 785 nm laser diode excitation. A significant enhancement of emission intensity at 1.81 μm with increasing concentration of Tm3+ ions has been observed while increasing the emission intensity at 2.0 μm with increasing concentration of Ho3+ has been observed up to the equal concentration of Tm3+ (0.5 mol%) in TBZLN glasses. The stimulated emission cross section of Tm3+: 3F4 → 3H6 (5.20 × 10-21 cm2) and Ho3+: 5I7 → 5I8 (4.00 × 10-21 cm2) in 1.0 mol% Tm3+-doped and 0.5 mol% Tm3+/1.0 mol% Ho3+-codoped TBZLN glasses are higher compared to the reported and are found to be excellent candidates for solid-state lasers operating at ~1.8 and 2.0 μm, respectively. The extension of NIR emission of Tm3+ with Ho3+ ions provides the possibility of using these materials for broadband NIR amplifiers. © 2016 American Ceramic Society and Wiley Periodicals, Inc