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
    UNISOFT – a program package for lattice-dynamical calculations (1987)
    Copenhagen : International Union of Crystallography (IUCr)
    Applied crystallography online 20 (1987), S. 134-139 
    Details
    ISSN: 1600-5767
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Geosciences , Physics
    Notes: The program package UNISOFT has been developed for lattice-dynamical calculations. Phonon dispersion curves can be calculated for any crystal structure with up to 20 atoms per primitive cell. The interaction between each individual pair of atoms can be modelled by one or more interaction types such as longitudinal and transverse springs (Born–von Karman model), Born–Mayer potential, Lennard-Jones potential, van der Waals potential, Coulomb potential, shell model. In addition to the model calculation part, UNISOFT contains several auxiliary programs dealing with group-theoretical analysis, neighbourhood analysis, plot of the phonon dispersion, calculation of partial derivatives, check of rotational invariance, calculation of local electrical fields and gradients, calculation of phonon intensities. In combination with a spectrometer for inelastic neutron scattering, UNISOFT provides a tool for the optimization of experiments as well as for a first interpretation of the results.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0021889887086977
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Electrogyration effect in alums (1976)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 32 (1976), S. 892-895 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: The electrogyration effect in 31 alums has been measured within the range 350 to 700 nm. The coefficients of electrogyration show an unexpectedly wide variation in alums of different composition and structural type. The effect is obviously related to the symmetry of the constituents and to their bonding interaction with water molecules. The dispersion of the electrogyration can be described by a formula which is also valid for natural optical activity. In contrast to other electro-optical effects Miller's rule does not apply for the electrogyration of the alums.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739476001770
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Electrogyration and piezogyration in NaClO3 (1979)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 35 (1979), S. 225-232 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: A method is developed for measuring electrogyration and piezogyration effects in polar crystals. The influence of linear electro-optic and piezo-optic effects is discussed in detail. By the use of different directions of measurement, the tensorial behaviour of the induced gyration is proved unequivocally. The magnitudes of the electrogyration and piezogyration coefficients are 10-16 m V-1 and 10-15 m2 N-1 respectively. The relations between constants measured under different thermodynamic conditions are considered. An analysis of results on the basis of a coupled oscillator model reveals a strong sensitivity of induced gyration to changes in the arrangement of the oscillators.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739479000383
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Anisotropic bond polarizabilities in birefringent crystals (1988)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 44 (1988), S. 320-326 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Based on the concept of bond polarizabilities the optical properties of a crystal are traced back to the orientation of its bonds and to the individual bond parameters \bar \betaand Δβ. A test with various sulfate compounds shows that the average bond parameters \bar \beta describe the average refractive indices with a higher accuracy than the traditional model of ionic polarizabilities. The anisotropic part of a bond polarizability, Δβ, is considered to be the origin of optical birefringence. Values for Δβ are evaluated in MCO3 and MSO4 (M = Mg, Ca, Sr, Ba). In different crystals the same values for Δβ have been discovered for the C-O and the S-O bonds. Δβ of the M-O bonds depends in a characteristic way on the bond length. A simple method is used to calculate local field effects in accordance with the model of bond polarizabilities. Possible applications of bond polarizabilities for the determination of structural quantities are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0108767387012492
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Polar Kerr effects and Magnetic circular dichroism in YBa"2Cu"3O"7"-"δ films
    Amsterdam : Elsevier
    Physica C: Superconductivity and its applications 216 (1993), S. 284-292 
    Details
    ISSN: 0921-4534
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0921-4534(93)90072-X
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Dispersion of the Voigt effect in the magnetic semiconductors Cd1−x MnxTe (1998)
    Springer
    JETP letters 67 (1998), S. 602-606 
    Details
    ISSN: 1090-6487
    Keywords: 75.50.Pp ; 78.20.Fm ; 78.20.Ls
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Spectral measurements of the Voigt birefringence Δn were performed for the cubic magnetic semiconductor Cd1−x Mn x Te (0≤x≤0.52) in order to investigate how the exchange interaction of Mn2+ ions with itinerant electrons depends on the electron wave vector. It was determined that Δn/x 2 is independent of x and the magnetic field direction, i.e., the effect is due to the Mn2+ ions and is isotropic. Below the band gap edge the dispersion of the birefringence Δn can be described well in all samples by the unusual dependence Δn∼(E g −ℏω) −3.5. This can be explained by a decrease of the exchange interaction of Mn2+ ions with itinerant electrons with increasing distance from the center of the Brillouin zone.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.567733
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Magnetically induced spatial dispersion in the cubic magnetic semiconductors Cd1−x MnxTe (1998)
    Springer
    Journal of experimental and theoretical physics 87 (1998), S. 553-562 
    Details
    ISSN: 1090-6509
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract In the transverse geometry we have detected birefringence that is linear in the magnetic field B and the light wave vector k in the cubic magnetic semiconductors Cd1−x MnxTe (0⩽x⩽0.52). The effect was found to be large, ∼1 (deg cm−1 T−1), and highly anisotropic, in contrast to the Faraday and Voigt effects. The phenomenon is represented by terms of type γ ijklBkkl in the permittivity tensor ε ij and can be described by two parameters, A and g. Spectral studies have shown that the normalized parameters A/x and g/x are independent of x, i.e., the effect can be related to the Mn2+ ions. Below the edge E g of the forbidden band, the dispersion of A is described by a (E g−E)−1.4-dependence, while the dispersion of g is nil. Theoretical analysis has shown that the spectral curves for A and g can be explained by the special features of the dispersion laws for electrons and holes (features related to the fact that there is no inversion center) and by the dependence of the parameters of the exchange interaction on the electron wave vector.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.558693
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Are ternary halides useful materials for nonlinear optical applications? (1996)
    Springer
    Applied physics 63 (1996), S. 67-74 
    Details
    ISSN: 1432-0630
    Keywords: 42.70 ; 42.70.Nq ; 78.20
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Ternary halides are potential materials for nonlinear optical applications in the mid infrared because of their transparency. We discuss physical, chemical and crystallographic aspects and develop a concept for preparing nonlinear optical halides. Based on the bond-charge model optical hyperpolarizabilities are calculated for more than one hundred A-X bonds where X = Cl, Br or I. The calculations are tested as far as possible by a comparison with experimental data. The tests show that the listed hyperpolarizabilities are a sound basis for the calculation of nonlinear optical susceptibilities in halides. A list of cations is given which form bonds with large hyperpolarizabilities and which show the tendency to form acentric structures. Phase diagrams of the two selected systems TII-AsI3 and TII-BiI3 are studied experimentally. Large single crystals of the new acentric compound Tl7Bi3I16 and of Tl3PbCl5 are prepared. In both crystals twinning prevents an effective SHG effect.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01579747
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    re ternary halides useful materialsfor nonlinear optical applications? (1996)
    Springer
    Applied physics 63 (1996), S. 67-74 
    Details
    ISSN: 1432-0630
    Keywords: PACS42.70; 42.70.Nq; 78.20
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract. Ternary halides are potential materials for nonlinear optical applications in the mid infrared because of their transparency. We discuss physical, chemical and crystallographic aspects and develop a concept for preparing nonlinear optical halides. Based on the bond-charge model optical hyperpolarizabilities are calculated for more than one hundred A-X bonds where X = Cl, Br or I. The calculations are tested as far as possible by a comparison with experimental data. The tests show that the listed hyperpolarizabilities are a sound basis for the calculation of nonlinear optical susceptibilities in halides. A list of cations is given which form bonds with large hyperpolarizabilities and which show the tendency to form acentric structures. Phase diagrams of the two selected systems TlI-AsI $_3$ and TlI-BiI $_3$ are studied experimentally. Large single crystals of the new acentric compound Tl $_7$ Bi $_3$ I $_{16}$ and of Tl $_3$ PbCl $_5$ are prepared. In both crystals twinning prevents an effective SHG effect.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01579747
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Manifestation of magnetically induced spatial dispersion in the cubic semiconductors ZnTe, CdTe, and GaAs (1999)
    Springer
    JETP letters 69 (1999), S. 551-557 
    Details
    ISSN: 1090-6487
    Keywords: 78.20.Fm ; 78.20.Ls ; 71.35.Gg
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Nonreciprocal birefringence due to magnetically induced spatial dispersion was observed in the T d-class cubic semiconductors ZnTe, CdTe, and GaAs near the fundamental absorption edge. The dispersion of the parameters A and g, describing the contributions from terms of the type B ikj to the diagonal and off-diagonal components of the permittivity tensor ε ij(ω,B,k), is determined for ZnTe and CdTe. Analysis of the dispersion and anisotropy of the nonreciprocal birefringence shows that in ZnTe, CdTe, and GaAs, in contrast to magnetic semiconductors of the type Cd1−x MnxTe, it is due excitonic mechanisms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.568066
    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...