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
    The electronic thermal conductivity of superconductors with paramagnetic impurities (1976)
    Springer
    The European physical journal 25 (1976), S. 339-349 
    Details
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We have measured the thermal conductivitiesK s in the superconducting state andK n in the normal state of (La1−x REx) Al2 single crystals (RE: Gd, Ce;x≦0.005) between 0.4 and 8 K. The lattice conductivity is small in the superconducting state above 0.5T c and in the normal state and is independent of annealing. Annealing does, however, strongly depress the ratioK s e /K n e of the electronic thermal conductivities. We also report on a theory of the electronic thermal conductivity which describes the experimental results quantitatively. Interaction effects between impurities show up for the samples with the highest RE-concentration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01315249
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Self-consistent theory of pairbreaking in kondo superconductors (1978)
    Springer
    The European physical journal 29 (1978), S. 39-46 
    Details
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract A theory is presented for the calculation of equilibrium properties of superconductors containing magnetic impuritiesof finite concentration. The theory is based on the Nagaoka-Suhl approach to thes — d model and treats finite impurity concentrations within a self-consistentT-matrix-approximation. An integral equation is derived for the pairbreaking parameter which describes de-pairing of Cooper pairs by spin flip scattering. Numerical solutions of this equation are used to compute the phase diagram in the temperature-concentration-plane and the transition-temperature-dependence of the upper critical field. These calculations are in good agreement with experimental data on LaCeAl2-samples. In addition, the recent discovery of three normal superconducting transitions in LaCeY is discussed quantitatively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01354836
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Green's function theory of the Kondo effect in dilute magnetic alloys (1968)
    Springer
    The European physical journal 212 (1968), S. 380-407 
    Details
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The exact solution of thet-matrix integral equation derived from the self-consistent Nagaoka equations in the theory of dilute magnetic alloys is established. It is shown that the unique solution for thet-matrix involving all Kondo type anomalies can be found under quite general assumptions. Using the exact solution we have calculated thermodynamic properties of dilute magnetic alloys. It is found that the excessive specific heat of the system due to the anomalous scattering of conduction electrons from the magnetic impurities is of the order ofBoltzmann's constant per local moment at low temperatures. In the limit of vanishing temperature the specific heat goes to zero asymptotically as (lnT)−4. Finally the entropy difference of the interacting system as compared to the free system is calculated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01380112
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Theory of magnetic impurities in superconductors. I (1970)
    Springer
    The European physical journal 232 (1970), S. 11-31 
    Details
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The Nagaoka Green's functions equations for a superconductor are solved exactly and the question of bound states within the gap is answered unambiguously. It is shown that there are always two bound states symmetrically located with respect to the center of the gap. For ferromagnetic coupling,γ〉0, and for antiferromagnetic coupling, butT K ≫T c0 orT K ≪T c0, these bound states are very close to the gap edges. ForT K ∼T c 0, however, the bound states move towards the center of the gap. It is pointed out that in the latter case important deviations from the Abrikosov-Gorkov theory, i.e. manifestations of the Kondo effect, should occur which could be tested experimentally by investigating the density of states.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01394943
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Spin correlation in dilute magnetic alloys (1969)
    Springer
    The European physical journal 223 (1969), S. 277-288 
    Details
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The correlation of a magnetic impurity spin with the spin density of the conduction electrons in a dilute magnetic alloy is calculated non-perturbationally on the basis of the Nagaoka theory. It is shown that there are anomalies due to the Kondo effect in the long range behaviour of this correlation which contradicts the bound state interpretation of the Kondo effect. The most interesting detail is the appearance of a non-oscillating contribution to the correlation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01392409
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Theory of magnetic impurities in superconductors (1972)
    Springer
    The European physical journal 256 (1972), S. 366-379 
    Details
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The jump of the specific heat at the transition temperature is calculated for a superconductor with magnetic impurities. The calculation includes the Kondo effect and is exact within the Nagaoka-approximation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01391983
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Theory of magnetic impurities in superconductors. II (1970)
    Springer
    The European physical journal 234 (1970), S. 58-69 
    Details
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The depression of the superconducting transition temperature due to the pair breaking effect of magnetic impurities is calculated exactly within the Nagaoka-Suhl approach to the Kondo problem in superconductors.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01392497
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Phase transitions of continuous order: Ising model on a Cayley tree (1975)
    Springer
    The European physical journal 22 (1975), S. 59-67 
    Details
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract We introduce the notion of a phase transition of continuous order. As a model which displays such a phase transition an Ising model on a Cayley tree is solved exactly and discussed in detail.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01325460
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Theory of magnetic impurities in superconductors (1976)
    Springer
    The European physical journal 23 (1976), S. 143-147 
    Details
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Ground state properties of a Kondo superconductor of low impurity concentration are calculated exactly within the Nagaoka approximation. The results for the location of the bound state motivate us to formulate the notion of intrinsic gaplessness. The order parameter, the ground state energy, and the thermodynamic critical field are computed. The relation to experiments and to the Hartree-Fock theory of magnetic impurities in a superconductor is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01352708
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Threshold exponents of pseudo-particle spectra of Kondo impurities (1988)
    Springer
    The European physical journal 73 (1988), S. 225-230 
    Details
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Pseudo-particle propagators or resolvents are known to be important ingredients in the theory of a degenerate Anderson impurity. At low temperatures they show conspicuous threshold behavior which is, however, described only approximately in perturbative theories like the non-crossing approximation. In this paper we derive the correct values of the threshold exponents from an argument due to Schotte and Schotte. For degeneracyN=1 we provide a complete perturbative proof of the validity of our results.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01305740
    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...