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
    Relaxation phenomena in polymer nonlinear optical materials (1991)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 70 (1991), S. 3251-3255 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The isothermal decay of the second-order nonlinear optical susceptibility of a guest-host azo dye methacrylate film was measured by second-harmonic generation at a series of temperatures. The decay curves were fit to Williams–Watt–Kohlrausch stretched exponentials. The activation energies and pre-exponential factors were found to agree with those derived from nonisothermal electric-field-induced second-harmonic generation measurements on similar films. It is concluded that a common underlying process involving a distribution of local relaxations governs the film behavior.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.349311
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    In situ, near-ideal epitaxial Al/AlxGa1−xAs Schottky barriers formed by molecular beam epitaxy (1990)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 68 (1990), S. 2239-2245 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The Schottky barrier height of in situ epitaxial aluminum on AlxGa1−xAs was measured as a function of aluminum mole fraction from x=0 to x=1, using I/V, C/V and activation energy plots of current-voltage dependence on temperature. The excellent electrical properties of the molecular beam epitaxy grown AlGaAs layers, with residual deep levels concentrations of less than 1014 cm−3 combined with the in situ deposition of single-crystal epitaxial aluminum resulted in extremely high quality Schottky diodes from x=0 (GaAs) to x=1 (AlAs) with accurately exponential current-voltage characteristics over up to 10 decades and with ideality factors less than 1.03. Both the C−2−V and activation energy plots were linear and yielded barrier heights in very good agreement with the I/V ones. The near-ideal characteristics of these diodes were compared with several models of Schottky barrier formation and the dependence of the Schottky barrier height on the aluminum mole fraction was found to agree with the anion vacancy model within 10–20 meV, with a maximum deviation of 46 meV.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.346528
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Double-barrier resonant tunneling structures incorporating superlattice energy filters (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 71 (1992), S. 3019-3024 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We have studied the electrical properties of GaAs/Al0.4Ga0.6As double-barrier resonant tunneling structures incorporating finite superlattices in the contact regions. The superlattices effectively act as energy filters defining the initial and final tunneling states. We have investigated an asymmetric device with one (emitter) superlattice and a symmetric device with two (emitter and collector) superlattices. These show significantly improved J(V) properties compared to other double-barrier structures and the superlattice tunnel diode.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.350984
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    A detailed Hall-effect analysis of sulfur-doped gallium antimonide grown by molecular-beam epitaxy (1990)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 68 (1990), S. 131-137 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Experimental data are presented for the Hall coefficient and the apparent Hall mobility over the temperature range 160–500 K for five samples of molecular-beam epitaxially grown sulfur-doped GaSb. The donor concentration of the different samples varied between 3.3×1017 and 7.5×1016 cm−3, and the native acceptor concentration between 8×1016 and 1.2×1016 cm−3. The samples show a large spread in the apparent carrier activation energy. A two valley compensated conduction model is presented that shows that the variation in apparent carrier activation energy results from different compensation ratios in the samples. This model also shows that the constant value of the Hall coefficient observed at high temperatures is not due to donor exhaustion but carrier promotion to the lower mobility L1 band. Using constraints provided by secondary ion mass spectrometry and capacitance-voltage measurements on the samples, as well as growth data, it is shown that a narrow spread of values for the donor binding energy around 60 meV is required to account for the data. It is suggested that this spread is due to the formation of a donor band and to the strongly attractive central cores of the sulphur donors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.347098
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Crosslinked polyimide electro-optic materials (1995)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 78 (1995), S. 5876-5883 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We report studies of the optical and electro-optic properties of guest–host polymeric nonlinear optical materials based on aromatic, fluorinated, fully imidized, organic soluble, thermally, and photochemically crosslinkable, guest–host polyimides. We have introduced temperature stable nonlinear optical chromophores into these polyimides and studied optical losses, electric field poling, electro-optic properties, and orientational stability. We measured electro-optic coefficients of 5.5 and 12.0 pm/V for ((2,6-Bis(2-(3-(9-(ethyl)carbazolyl))ethenyl)4H-pyran-4-ylidene)propanedinitrile (4-(Dicyanomethylene)-2-methyl-6-(p -dimethylaminostyryl)-4H-pyran) DCM-doped guest–host systems at 800 nm using a poling field of 1.3 MV/cm. Poling induced nonlinearities in single-layer films were in agreement with the oriented gas model, but were lower in three-layer films due to voltage division across the layers. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.360779
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Loss mechanisms in polyimide waveguides (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 2505-2508 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Waveguide losses in thin film polyimides using waveguide loss spectroscopy and photothermal deflection spectroscopy as a function of cure cycle and structure were studied. Fluorinated sidegroups on the polyimide backbone lead to decreases in birefringence and absorption. The primary waveguide loss mechanism is absorption, not scattering. Waveguide losses as low as 0.4 dB/cm at 800 nm have been measured. Losses as low as 0.3 dB/cm at 1300 nm can be inferred from the photothermal deflection spectroscopy.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.357610
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Homogeneous photorefractive polymer/nematogen composite (1998)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 72 (1998), S. 2948-2950 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A photorefractive composite consisting of the polymer poly(N-vinylcarbazole) (PVK) doped with 4,4′-n-pentylcyanobiphenyl (5CB) and C60 is reported. The material shows no sign of phase separation, is stable, and does not require a plasticizer agent. Gain coefficients over 100 cm−1 are observed. Measurements of orientational and electro-optic responses indicate that the orientational response is large, but markedly inhibited. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.121503
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Electro-optic phase modulation and optical second-harmonic generation in corona-poled polymer films (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 53 (1988), S. 1800-1802 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Electro-optic phase modulation was measured along with optical second-harmonic generation in thin films of a new copolymer containing a dicyanovinyl-terminated azo dye side chain. Orientational order was imparted to these films by poling with a corona discharge. Details of the electro-optic measurement technique, in which the real part of the electro-optic coefficient can be determined directly, are presented. Taking advantage of the increased orientation imparted by corona poling and the hindered motion of the nonlinear optical moiety in the side chain of the polymer leads to substantial improvements in both the magnitude and stability of nonlinear optical susceptibilities compared to guest-host polymer systems ordered by electrode poling.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.99785
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Deep donors in GaSb grown by molecular beam epitaxy (1990)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 57 (1990), S. 1645-1647 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A deep state possessing similar properties to those reported for DX centers in the AlGaAs system has been observed at atmospheric pressure in GaSb moderately doped with sulfur. The first detailed deep level transient spectroscopy study of this material has revealed a large energy barrier to electron capture and a correspondingly small capture cross section for this deep level. The deep level activity of selenium- and tellurium-doped GaSb has also been investigated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.104075
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Effect of the detailed growth conditions on the injection efficiency of (N)AlGaAs-(p+)GaAs heterojunctions produced by molecular-beam epitaxy (1989)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 65 (1989), S. 5177-5180 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Abrupt (N)AlGaAs-(p+ )GaAs heterojunction diodes were grown by molecular-beam epitaxy. It was found that the position with respect to the heterointerface at which the substrate temperature was changed from that for the growth of (p+ )GaAs to that for the growth of (N)AlGaAs had a significant effect on the injection efficiency of the devices. By initiating the substrate temperature rise right at the start of the (N)AlGaAs growth, heterojunction bipolar transistors with an abrupt (N)Al0.18 Ga0.82 As-(p+ )GaAs emitter-base junction having current gains of between 60 and 70 were fabricated. These relatively high-current gains are argued to be due to the effects of hot-electron injection into the base.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.343146
    Location Call Number Expected 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...