Unconventional magnonic surface and interface states in layered ferromagnets

Interface Motion in Disordered Ferromagnets

We consider numerically the depinning transition in the randomfield Ising model. Our analysis reveals that the three and four dimensional model displays a simple scaling behavior whereas the five dimensional scaling behavior is affected by logarithmic corrections. This suggests that d = 5 is the upper critical dimension of the depinning transition in the random-field Ising model. Furthermore, w...

Unconventional Superconductivity in Layered Organic Superconductors

Like the high-Tc copper oxides, organic superconductors are another class of superconductors that cannot be fully explained by the conventional BCS theory, due to the repulsive effective interactions between the charge carriers. Experiments display similarities between these systems and the high-Tc copper oxides in their pairing symmetry and their phase diagram. In this paper, some results from...

SoftMagnetorotons and Broken-Symmetry States in BilayerQuantumHall Ferromagnets

The recent report on the observation of soft magnetorotons in the dispersion of charge-density excitations across the tunneling gap in coupled bilayers at total Landau level filling factor νT = 1 is reviewed. The inelastic light scattering experiments take advantage of the breakdown of wave-vector conservation that occurs under resonant excitation. The results offer evidence that in the quantum...

Metastable states in spin glasses and disordered ferromagnets.

We study analytically M-spin-flip stable states in disordered short-ranged Ising models (spin glasses and ferromagnets) in all dimensions and for all M. Our approach is primarily dynamical, and is based on the convergence of sigma(t), a zero-temperature dynamical process with flips of lattice animals up to size M and starting from a deep quench, to a metastable limit sigma(infinity). The result...

Electronic States of Graphene-Based Ferromagnets