相关论文: Quantum Spin Systems: From Spin Gaps to Pseudo Gap…

Lanthanum family of high-temperature cuprate superconductors is known to exhibit both spin and charge electronic modulations around doping level 1/8. We assume that these modulations have the character of two-dimensional spin-vortex…

The Raman scattering spectra from magnetic excitations in an antiferromagnetic spin-1/2 two leg ladder is investigated for weak and strong interladder coupling. In the first case, a cusp in the Raman intensityis obtained at a frequency…

We report density-matrix renormalization group calculations of spin gaps in the quarter-filled correlated two-leg rectangular ladder with bond-dimerization along the legs of the ladder. In the small rung-coupling region, dimerization along…

We consider spin dynamics in the impurity band of a semiconductor with spin-split spectrum. Due to the splitting, phonon-assisted hops from one impurity to another are accompanied by rotation of the electron spin, which leads to spin…

We theoretically describe the phenomenon of non-adiabatic spin dynamics, which occurs in a gas cell filled by alkali vapor in presence of a strong alternating magnetic field and pump light. Steep increase of the spin polarization occurs if…

A systamatic quantitative comparison of ''pseudogap'' values obtained from the analysis of charge and spin excitation spectroscopies in underdoped YBa2Cu3O7-x using a temperature-independent gap shows two distinct excitations, one visible…

We provide evidence for spin glass related magnetic gaps in the fermionic density of states below the freezing temperature. Model calculations are presented and proposed to be relevant for explaining resistivity measurements which observe a…

The mineral malachite, Cu2(OD)2CO3, has a quantum spin-liquid ground state and no long-range magnetic order down to at least T=0.4 K. Inelastic neutron scattering measurements show that the excitation spectrum consists of dispersive gapped…

We study the properties of spin systems realized by cold polar molecules interacting via dipole-dipole interactions in two dimensions. Using a spin wave theory, that allows for the full treatment of the characteristic long-distance tail of…

We study theoretically the spin transport in a nonmagnetic metal connected to ferromagnetic injector and detector electrodes. We derive a general expression for the spin accumulation signal which covers from the metallic to the tunneling…

The spinon and holon excitations of two-leg Heisenberg or lightly doped t-J ladders are shown to be bound in pairs by string confinement forces given approximately by the antiferromagnetic exchange energy across the rungs. These forces…

The current theoretical and experimental situation is reviewed for low-dimensional (layered and chain-like) insulating systems. Such systems possess a low magnetic transition temperature $T_M$ and pronounced short-range magnetic order above…

The current theoretical and experimental situations are reviewed for low-dimensional insulating systems with a low magnetic transition temperature TM and pronounced short-range magnetic order above this temperature. Both the standard and…

Low dimensional spin-1/2 systems with antiferromagnetic interactions display very innovative features, driven by strong quantum fluctuations. In particular, geometrical effects or competing magnetic interactions can give rise to the…

The underdoped cuprate superconductors are characterized by the opening of the pseudogap, while such an aspect of the pseudogap effect should be reflected in the low-energy electronic structure (LEES). Here the effect of the pseudogap on…

We introduce a new Kondo ladder model by coupling the well-known Takhtajan-Babujan S=1 chain to a half-filled one-dimensional electron gas, and we solve it using quantum field theory techniques. Through the so-called underscreened Kondo…

Using a SU(2)x U(1) gauge theory for a t-J model around a node of the Fermi surface, we discuss patterns of dynamical symmetry breaking, which may lead to a pseudogap phase and to the appearance of narrow one-dimensional spatial structures,…

The recently discovered Fe-pnictide and chalcogenide superconductors display low-temperature properties suggesting superconducting gap structures which appear to vary substantially from family to family, and even within families as a…

Spectroscopic measurements with low-temperature scanning tunneling microscopes have been used very successfully for studying not only individual atomic or molecular spins on surfaces but also complexly designed coupled systems. The symmetry…

We argue that strongly correlated two dimensional electrons form a spin liquid in some regimes of density and temperature and give the theory of the magnetic properties of this spin liquid using the representation in terms of femions…