Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Luminescence Properties of a Multi-Component Glass Co-Implanted with Si and Er (2004)
    s.l. ; Stafa-Zurich, Switzerland
    Solid state phenomena Vol. 99-100 (July 2004), p. 37-40 
    Details
    ISSN: 1662-9779
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Physics
    Notes: The incorporation of Si-nc in Er doped silica is known to strongly enhance the infrared luminescence of Er3+ at 1.54µm. The enhancement is believed to be due to an energy transfer process from Si-nc to Er. In this work we investigate the formation of Si nano-aggregates and their role in the energy transfer process to Er3+ ions for a multi-component glass host. These materials can offer better performances than silica in terms of Er solubility and band broadness for integratedEr-doped optical amplifiers and investigation is therefore very interesting for optoelectronic applications. Si and Er were co-implanted by choosing the implantation energies in order to optimize the overlap between the concentration profiles. The precipitation of Si and the enhancement of the 1.54 µm Er emission were studied for different post-implantation annealing temperatures. In particular the optical properties of the glass were investigated by means of photoluminescence (PL) spectroscopy and the results are discussed in relation to a standard silicasubstrate. These data are presented and related to the structural properties of the material. Moreover the implications on the future development of an Er doped optical amplifier are discussed
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/26/transtech_doi~10.4028%252Fwww.scientific.net%252FSSP.99-100.37.pdf
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Bleaching mechanism of silver halide photochromic glasses (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 1657-1668 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Thermal bleaching of silver halide photochromic glasses is studied by electron paramagnetic resonance spectroscopy of photoinduced CuII centers. During exposure to ultraviolet light, the only stable CuII species is the (CuIIVAg)A center, which is a CuII-silver vacancy complex with the vacancy in a nearest position. In the dark, this center rapidly decays via two parallel channels. The first involves the dissociation of the complex by displacement of the vacancy along a [110] direction, with an activation energy E3=0.44 eV and a frequency factor k30=3.4×105 s−1. The second channel involves the conversion of the (CuIIVAg)A center into a (CuIICl−VAg)B center, where the silver vacancy is in the next nearest position along the [100] direction. This process occurs with an activation energy E1=0.44 eV and a frequency factor k10=3.1×105 s−1. The (CuIICl−VAg)B center slowly decays by a vacancy hopping mechanism, with an activation energy E2=0.22 eV and a frequency factor k20=4.6 s−1. To explain these two decay channels, it is proposed that the (CuIIVAg)A and (CuIICl−VAg)B centers annihilate via the formation of a CuI ion and a neutral complex (AgIIVAg)A which migrates to the surface of the silver halide particle, where electron-hole recombination occurs.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.353200
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Electron-paramagnetic-resonance study of silver halide photochromic glasses: Darkening mechanism (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 71 (1992), S. 1081-1090 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The mechanism of darkening of standard silver halide photochromic glass is studied by electron paramagnetic resonance (EPR) of photogenerated divalent copper ions. A time resolution of the EPR spectra was obtained by recording the evolution with the irradiation time of the EPR intensity at various magnetic-field strengths. It is shown that only one copper species is photogenerated during darkening. This species is a CuII-silver vacancy complex oriented along a [110] direction. The electron ground state has a predominantly dz2 character. The activation energy of the formation of this complex, E=0.06±0.01 eV, is controlled by the migration of interstitial silver ions. It is also shown that the silver vacancy of the complex is generated during the hole trapping by the monovalent copper ion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.351400
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Synthesis of monolithic silica gels by hypercritical solvent evacuation (1984)
    Springer
    Journal of materials science 19 (1984), S. 1656-1665 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The method of obtaining monolithic dry gels by hypercritical solvent evacuation is presented. The influence of various parameters on the possibility of obtaining crack-free pieces is studied in some detail. The influence of these parameters on the final properties of the gel is also discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00563063
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Glasses from aerogels (1990)
    Springer
    Journal of materials science 25 (1990), S. 3118-3126 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Silica glasses are obtained by the densification of aerogels. The transformation of the material into a glass is followed by differential thermal analyis, thermo-gravimetric analysis, dilatometry and by the evolution of the structural, textural and mechanical properties of the material. The organic species and the hydroxyl groups are removed by oxidation and chlorination heat treatments in such a way as to avoid bloating and crystallization phenomena during sintering. Densification is obtained by heat treatment at a low temperature (1100 to 1300 ° C). The densified aerogel shows physical properties identical to those of molten silica. Moreover, this material is very pure and its water content is low. The same process can be extrapolated to multicomponent glasses and composite materials.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00587660
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Glasses from aerogels (1990)
    Springer
    Journal of materials science 25 (1990), S. 3111-3117 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Experiments carried out to obtain monolithic silica aerogels are reported. The different ways to synthesize silica aerogels from alkoxides are investigated. The manner by which the critical point of the solvent can be reached is discussed as a function of the nature of the solvent. Physical parameters such as the amount of additional solvent or pressure, play a very important role in the direction of the liquid-vapour interface displacement during the heating of the autoclave. Some experiments performed using hypercritical drying with CO2 liquid are also mentioned.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00587659
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Synthesis of glasses from gels: the problem of monolithic gels (1982)
    Springer
    Journal of materials science 17 (1982), S. 3371-3379 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The synthesis of glasses from gels has recently aroused considerable interest both from the theoretical and practical standpoint. The conditions of gel formation which determine the structure of the wet gel are first examined. During the drying process, which is a decisive step in the obtention of monolithic gels, an essential role is played by capillary forces. It is shown that, among the various methods of obtaining monolithic gels, that based on the hypercritical evacuation of the solvent is the most reliable.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01203507
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...