Zobrazeno 1 - 10
of 456
pro vyhledávání: '"Oppermann R"'
Effects of the spin-orbit interactions on the energy spectrum, Fermi surface and spin dynamics are studied in structural- and bulk-inversion asymmetric quasi-two-dimensional structures with a finite thickness in the presence of a parabolic transverse
Externí odkaz:
http://arxiv.org/abs/1103.2036
Autor:
Nakhmedov, E., Oppermann, R.
Publikováno v:
Published in Phys. Rev. B 81, 134511 (2010)
Effects of non-magnetic disorder on the critical temperature T_c and on diamagnetism of quasi-one-dimensional superconductors are reported. The energy of Josephson-coupling between wires is considered to be random, which is typical for dirty organic
Externí odkaz:
http://arxiv.org/abs/1103.1806
Autor:
Nakhmedov, E. P., Oppermann, R.
Publikováno v:
Published in JETP Lett. 91, 570 (2010)
Effects of non-magnetic randomness on the critical temperature T_c and diamagnetism are studied in a class of quasi-one dimensional superconductors. The energy of Josephson-coupling between wires is considered to be random, which is typical for dirty
Externí odkaz:
http://arxiv.org/abs/0911.1253
Autor:
Oppermann, R., Schmidt, M. J.
This article reviews recent years' progress in the low temperature analysis of standard models of spin glass order such as the Sherrington-Kirkpatrick (SK) model. Applications to CdTe/CdMnTe layered systems and explanation of glassy antiferromagnetic
Externí odkaz:
http://arxiv.org/abs/0707.2883
Publikováno v:
PHYSICAL REVIEW B Volume: 76 Issue: 12 Article Number: 125206 Published: 2007
A numerical technique is developed to solve the Luttinger-Kohn equation for impurity states directly in k-space and is applied to calculate bound hole wave functions in a ferromagnetic (Ga,Mn)As host. The rich properties of the band structure of an a
Externí odkaz:
http://arxiv.org/abs/0704.2028
Autor:
Oppermann, R., Sherrington, D.
Using numerical self-consistent solutions of a sequence of finite replica symmetry breakings (RSB) and Wilson's renormalization group but with the number of RSB-steps playing a role of decimation scales, we report evidence for a non-trivial T->0-limi
Externí odkaz:
http://arxiv.org/abs/cond-mat/0509700
Time to look for evidence: Results-based approach to biodiversity conservation on farmland in Europe
Autor:
Herzon, I., Birge, T., Allen, B., Povellato, A., Vanni, F., Hart, K., Radley, G., Tucker, G., Keenleyside, C., Oppermann, R., Underwood, E., Poux, X., Beaufoy, G., Pražan, J.
Publikováno v:
In Land Use Policy February 2018 71:347-354
Autor:
Bechmann, M., Oppermann, R.
We consider quantum-dynamical phenomena in the $\mathrm{SU}(2)$, $S=1/2$ infinite-range quantum Heisenberg spin glass. For a fermionic generalization of the model we formulate generic dynamical self-consistency equations. Using the Popov-Fedotov tric
Externí odkaz:
http://arxiv.org/abs/cond-mat/0407328
Autor:
Bechmann, M., Oppermann, R.
We study a fermionic version of the Sherrington-Kirkpatrick model including nearest-neighbor hopping on a $\infty$-dimensional simple cubic lattices. The problem is reduced to one of free fermions moving in a dynamical effective random medium. By mea
Externí odkaz:
http://arxiv.org/abs/cond-mat/0306720
Autor:
Oppermann, R., Sherrington, D.
Models with range-free frustrated Ising spin- and Hubbard interaction are treated exactly by means of the discrete time slicing method. Critical and tricritical points, correlations, and the fermion propagator, are derived as a function of temperatur
Externí odkaz:
http://arxiv.org/abs/cond-mat/0207734