ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    Local structure analysis of an optically active center in Er-doped ZnO thin film (2001)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 89 (2001), S. 3679-3684 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The local structure of an optically active center in erbium-doped zinc oxide (ZnO:Er) thin film produced by a laser ablation technique and its optical activation process are investigated by Er LIII-edge x-ray absorption fine structure analysis using a synchrotron radiation as an x-ray source. In as-ablated ZnO:Er thin film, Er has an approximately five-fold coordination of O surrounded by eight other O atoms as second-nearest neighbors. The high-order coordination of O decreases the Er-related photoluminescence (PL) intensity due to an undesirable crystal field for 4f radiation transition. After annealing in O2 ambient, the local structure of Er changes to a pseudo-octahedral structure with C4v symmetry, similar to the optically activated Er-doped Si (Si:Er), resulting in strong PL. The bond lengths of Er–O are evaluated, and differences in the optical activation processes between ZnO:Er and Si:Er thin films are discussed. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1355284
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    X-ray induced photoemission of a localized electron and its application to site-selective x-ray absorption fine structure measurement (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 88 (2000), S. 3962-3967 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: For local structure analyses of carrier trap centers in semiconductors, site-selective x-ray absorption fine structure (XAFS) measurement, the "capacitance XAFS" method, is proposed. The concept of capacitance XAFS measurement is based on the fact that the amount of x-ray absorption of trap centers, not the bulk, may be evaluated from the capacitance change due to x-ray induced photoemission of a localized electron. In order to verify this model, characteristics of x-ray induced photoemission from defects are investigated by capacitance–voltage measurement. The temperature dependence of the photocarrier concentration in a semiconductor corresponds to that of the capacitance XAFS signal amplitude. On the other hand, no influence of the thermal excitation of defects on the capacitance XAFS signal amplitude is observed. These results indicate that the capacitance XAFS signal originates from localized electron emission via the inner-shell excitation of defect atoms, resulting in site selectivity to the trap centers. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1308098
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The optically active center and its activation process in Er-doped Si thin film produced by laser ablation (1999)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 85 (1999), S. 4024-4031 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The local structure of erbium-doped silicon produced by the laser ablation technique is investigated by Er LIII-edge x-ray absorption fine structure analysis. The combined analysis of extended x-ray absorption fine structure analysis and an x-ray absorption near-edge structure simulation based on multiple-scattering theory reveals the most probable atomic coordination of the optically active center; Er bonded with six oxygen atoms has a C4v symmetry. The optical activation process of this system is also discussed. The Si target with 10 wt% Er2O3 has two kinds of local structures, C-rare-earth Er2O3 grain and another Er phase incorporated in Si. The laser ablation homogenizes these phases, and deposits a new single-phase structure of the octahedron (Oh point group) on the substrates. In this phase, the optical transition probability is low due to the forbidden 4f transition of Er in the crystal field originating from the higher-order symmetry of O. After annealing, degradation of the symmetry from Oh to C4v results in a crystal field suitable for inducing sufficient radiation transition. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.370306
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Theoretical prediction of local distortion in an ErO6 cluster: Stabilization of a C4v structure by a rack and pinion effect (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 79 (2001), S. 934-936 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: As a possible atomic coordination of erbium dopants surrounded by oxygen, a molecular orbital calculation of an ErO6 cluster can predict a C4v pseudo-octahedral structure with Er distortion of ∼0.1 Å from the octahedral center. It was found that bond alternation by a "rack and pinion effect" can minimize the electron transfer from O2− to Er3+ at this distortion range, resulting in stable ionic bonding; the rotation of an O 2p orbital due to Er 5d translation, similar to rack and pinion motion, forms a new O 2p–Er 5d bond, while a dipole moment induced by symmetrical degradation makes an O 2p–Er 6s bond unstable. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1392305
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Site-selective x-ray absorption fine structure analysis of an optically active center in Er-doped semiconductor thin film using x-ray-excited optical luminescence (2001)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 183-185 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In order to discuss the local structure of an optically active center in Er-doped Si thin film, site-selective x-ray absorption fine structure (XAFS) analysis using x-ray-excited optical luminescence was performed. The XAFS spectrum at the Er LIII edge was obtained from the x-ray photon energy dependence of the peak intensity of infrared luminescence due to Er intra-4f transition. Although conventional XAFS measurement analyzes the average structure of all of the Er, this method intrinsically provides structural information for only optically active Er. A broad 2p–5d resonant peak in the site-selective XAFS spectrum is reproduced by a density-of-state calculation of a distorted ErO6 cluster, assuming an Er transformation from an octahedral center of 0.25 Å. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1336546
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Observation and control of surface morphology of AlP grown by atomic layer epitaxy (1997)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 71 (1997), S. 1044-1046 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The surface of the epitaxial layer of AlP grown by atomic layer epitaxy (ALE) was observed by atomic force microscopy. It was discovered that the atomic scale surface flatness was not always retained during ALE growth even though the self-limiting growth of 1 monolayer per 1 alternative source gas supply was maintained. A reaction process model that focused on the methyl adsorbate lifetime on the Al surface was proposed to explain the experimental results. Based on this model, AlP surface morphology was improved by gas feeding control, and a flat surface with atomic steps was obtained even after 250 cycles of the ALE sequence. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.119722
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Site-selective x-ray absorption fine structure: Selective observation of Ga local structure in DX center of Al0.33Ga0.67As:Se (1999)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 74 (1999), S. 2672-2674 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: In order to discuss the local structure of deep level carrier traps, the site-selective x-ray absorption fine structure (XAFS) by measuring the x-ray photon-energy dependence of the capacitance of a Schottky barrier diode is proposed. Dropping of the localized electron into a core hole arising from x-ray absorption of the atom in the carrier trap, not in bulk, increases the capacitance. The site-selective XAFS is adopted for the local structure analysis of DX center in Al0.33Ga0.67As:Se. The Ga K-edge site-selective XAFS is different from the conventional XAFS, suggesting that Ga in the DX center with a large lattice relaxation is selectively observed. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.123951
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Rapid and sensitive XAFS using a tunable X-ray undulator at BL10XU of SPring-8 (2000)
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 7 (2000), S. 89-94 
    Details
    ISSN: 1600-5775
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: The design and performance of the high-brilliance XAFS facility at BL10XU of SPring-8, aimed at rapid and sensitive measurement of X-ray absorption fine structure (XAFS), is reported. Both undulator gap and double-crystal monochromator have been successfully controlled covering a wide energy range (5–30 keV). A versatile goniometer system, consisting of two independent high-precision goniometers, is capable of polarized XAFS in fluorescence mode and surface-sensitive experiments using a grazing-incidence geometry. By sharing major components, i.e. a monolithic Ge 100-pixel array detector and a closed-cycle He cryostat, both polarized XAFS and X-ray standing wave (XSW) experiments can be performed at low temperature (15–300 K). The performance of the spectrometer has been evaluated by recording XAFS spectra in transmission mode.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0909049599016817
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Capacitance XAFS method: X-ray absorption spectroscopy of low-dimensional structures (2001)
    Chester : International Union of Crystallography (IUCr)
    Journal of synchrotron radiation 8 (2001), S. 331-333 
    Details
    ISSN: 1600-5775
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: For local structure analyses of low-dimensional structures in semiconductors, such as defects, interfaces and surfaces, a new site-selective X-ray absorption fine structure (XAFS) measurement, `capacitance XAFS method', is presented. This method measures the X-ray photon energy dependence of the capacitance involved in diode structures. Since the capacitance is changed by an X-ray induced photoemission of localized electrons in the low dimensional structures, a site-selective analysis can be made. Although macroscopic X-ray absorption can be measured by conventional XAFS analyses, low-dimensional X-ray absorption coefficients are observed by the capacitance XAFS measurements.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0909049500014424
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    facet.materialart.
    Unknown
    Charge propagation dynamics at trapping centers that induce the luminescence of rare-earth dopants in wide-gap materials (2011)
    American Institute of Physics
    Details
    Publication Date: 2011-09-05
    Print ISSN: 0003-6951
    Electronic ISSN: 1077-3118
    Topics: Physics
    Published by American Institute of Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...