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
    Magnetic neutron scattering in single crystal Bi2CuO4 : 37th Annual conference on magnetism and magnetic materials (1993)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 73 (1993), S. 6448-6450 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The spin-wave excitations and the critical behavior of the sublattice magnetization in Bi2CuO4 have been investigated by means of neutron scattering. The three-dimensional character of the antiferromagnetic ordering with propagation vector K=(1,0,0) below TN=45.83(8) K is reflected by the value of the critical exponent β=0.352(3). The spin-wave excitations have been measured along the symmetry directions [100] and [001]. The spin-wave dispersion is found to split into two branches with energy gaps Δ1=2.1 meV and Δ2=3.4 meV at the zone center. The data analysis is based on an S=1/2 spin Hamiltonian of tetragonal symmetry with anisotropic bilinear exchange including a four-site exchange interaction term.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.352629
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Four-spin exchange in Bi2CuO4 (abstract) : 38th Annual Conference on Magnetism and Magnetic Materials (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 75 (1994), S. 6743-6743 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Magnetic properties of Bi2CuO4 single crystals are of interest owing to their relationship to the high-Tc superconductor problem. Earlier we carried out the magnetic and neutron scattering investigations on high quality large single crystals. The Bi2CuO4 crystal belongs to the space group P4/ncc and the magnetic group is the collinear plane antiferromagnet with a Neel temperature of 45.8 K. The three-dimensional character of the antiferromagnetic ordering is reflected by the value of the critical magnetization exponent 0.352. The sublattice magnetization depends very little on temperature up to about 15 K. The spin-wave spectrum contains two branches with energy gaps of 2.1 and 3.4 meV. The theoretical interpretation of the experimental data shows the necessity of introducing the tensor four-site exchange in the S=1/2 spin Hamiltonian with the tetragonal anisotropic bilinear exchange. This provides the gap characteristics of the acoustic branch of spin waves and the correct temperature dependence of the sublattice magnetization. This result shows the importance of the four-site exchange for the formation of Bi2CuO4 magnetic properties. From the similarity of magnetic subsystems, Bi2CuO4, and high-Tc superconductors it is suggested that the four-site exchange is responsible for magnetic ordering of the square spin S=1/2 lattice. We also suggest a thermodynamic theory of the temperature dependence of magnetic properties of Bi2CuO4.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.356860
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Investigation of spin waves in single crystal Bi"2CuO"4 by inelastic neutron scattering
    Amsterdam : Elsevier
    Solid State Communications 82 (1992), S. 443-446 
    Details
    ISSN: 0038-1098
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0038-1098(92)90746-V
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Magnetic structure and magnetic field behaviour of NaMnCl"3
    Amsterdam : Elsevier
    Journal of Magnetism and Magnetic Materials 15-18 (1980), S. 539-541 
    Details
    ISSN: 0304-8853
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/0304-8853(80)91166-X
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Influence of the transport current on the magnetoelectric properties of La0.7Pb0.3MnO3 single crystals with giant magnetoresistance in the microwave region (1999)
    Springer
    Physics of the solid state 41 (1999), S. 1842-1849 
    Details
    ISSN: 1063-7834
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The results of experiment on the influence of a direct current and a low-frequency alternating current, as well as a magnetic field, on the microwave-range conductivity σ MW of Ln0.7Pb0.3MnO3 single crystals with giant magnetoresistance are presented. The greatest sensitivity of the samples toward the effects of a current is observed in the temperature range corresponding to the dc magnetoresistance maximum. The response signal of a sample in the microwave range to the effects of an alternating current of a low frequency f 0 has a nonlinear character. As f 0 is varied in a magnetic field, the amplitude of the response signal varies with the appearance of resonance peaks. The results obtained are interpreted within an approach based on the coexistence of two phases having different conductivities in the doped manganite crystals. This two-phase interpretation is supported by data from magneticresonance investigations, which demonstrate the existence of two magnetic phases over a broad temperature range in Ln0.7Pb0.3MnO3 single crystals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.1131111
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Synthesis and magnetic properties of Cu3B2O6 single crystals (1999)
    Springer
    Physics of the solid state 41 (1999), S. 610-612 
    Details
    ISSN: 1063-7834
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The temperature dependence of the magnetic susceptibility of Cu3B2O6 single crystals grown by spontaneous crystallization from a melt consisting of a mixture of CuO and B2O3 and the behavior of their magnetization are investigated in magnetic fields up to 55 kOe. A broad susceptibility maximum is observed near 39 K, and a sharp drop in susceptibility is observed at T〈10 K. The paramagnetic Néel temperatures for all orientations of the magnetic field in the crystal investigated are negative, attesting to the predominantly antiferromagnetic character of the exchange interactions. The effective magnetic moment of the Cu2+ ion is anisotropic and lies in the range from 1.054μ B to 1.545μ B. The magnetization depends linearly on magnetic field at T〉10 K, whereas at temperatures below 10 K a discontinuity is observed at fields of the order of 40 kOe. At room temperature, electron magnetic resonance characterized by an almost isotropic g factor (g=2.165) is detected at 36.22 GHz. The exchange interactions in Cu3B2O6 are analyzed on the basis of the Goodenough-Kanamori rules. The possibility of the establishment of a singlet magnetic state in the crystal is analyzed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.1130835
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Magnetostriction of the spin-Peierls magnet CuGeO3 (1998)
    Springer
    Physics of the solid state 40 (1998), S. 1520-1522 
    Details
    ISSN: 1063-7834
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The temperature dependence of the longitudinal magnetostriction of a CuGeO3 single crystal is measured within the temperature range 4.2–20 K in a magnetic field of 10 T. As the temperature is raised above 4.2 K, the magnetostriction at first increases from vanishingly small values, attains a maximum at a temperature of approximately 12 K, and then abruptly drops as the temperature approaches the spin-Peierls transition. The results are interpreted on the basis of a simple model utilizing the real pattern of magnetic excitations in the spin system.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.1130590
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Antiferromagnetic resonance in CuB2O4 single crystal (2000)
    Springer
    Physics of the solid state 42 (2000), S. 96-102 
    Details
    ISSN: 1063-7834
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The frequency-field, temperature, and angular dependences of the antiferromagnetic resonance parameters for the tetragonal CuB2O4 single crystal are studied in the frequency range 2.6–80 GHz and at temperatures of 4.2–30 K. The results obtained confirm the fact that, in the high-temperature state in the range 10–21 K, this compound is an easy-plane weak ferromagnet. The temperature dependence of the Dzyaloshinski field is determined. An abrupt change observed in the frequency-field dependence of the magnetic resonance at T=4.2 K and H ⊥ C 4 indicates the transition to the weak ferromagnetic state induced by the external field H ⊥. The phase diagram for CuB2O4 is constructed on the H ⊥-T coordinates. It is demonstrated that, in the low-temperature state, the magnetic moments of copper ions remain in the basal plane, but the weak ferromagnetism is absent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.1131174
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Magnetic susceptibility and magnetic-field behavior of CuB2O4 copper metaborate (2000)
    Springer
    Physics of the solid state 42 (2000), S. 321-325 
    Details
    ISSN: 1063-7834
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract An experimental study is reported regarding the temperature dependence of the magnetic susceptibility of a CuB2O4 tetragonal single crystal within the 4.2–200-K range. It has been established that the magnetic susceptibility exhibits anomalies at 21 and 10 K and depends strongly on crystal orientation in the magnetic field. A study has been carried out of the field dependences of the magnetization of CuB2O4 at various temperatures and crystal orientations. It is shown that for T〉21 K, the crystal is in a paramagnetic state determined by Cu2+ copper ions with an effective magnetic moment of 1.77 µB. Within the 10–21 K interval, the field dependence of the magnetization is typical of a weak ferromagnet with magnetic moments of the two antiferromagnetically coupled sublattices lying in the tetragonal plane of the crystal. The spontaneous weakly-ferromagnetic moment is 0.56 emu/g at 10 K. The canting angle of the sublattice magnetic moments, determined by the Dzyaloshinski-Moriya interaction, is 0.49°. It is believed that below 10 K, the CuB2O4 crystal retains its easy-plane magnetic structure, but with a zero spontaneous magnetic moment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.1131205
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Orbital ordering in CuGeO3 (1998)
    Springer
    Physics of the solid state 40 (1998), S. 1534-1539 
    Details
    ISSN: 1063-7834
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The combined effect of the ligand crystal field and the exchange interaction on the Cu2+ cation in CuGeO3 is examined. It is shown that, if the magnitude of the exchange interaction exceeds the splitting of the energy levels of the $$d_{x^2 - y^2 } $$ and d xy orbitals, then an alternate filling of the d orbitals along a chain (orbital ordering) is possible. This effect creates an antiferromagnetic interaction between Cu2+ pairs in 90° exchange and a doubling of the lattice period. A Jahn-Teller pseudoeffect causes singletization of the ground state of the antiferromagnetic chain of Cu2+ spins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1134/1.1130602
    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...