Related papers: Quantum Spin Fluctuations as a Source of Long-Rang…
We derive new general expressions for the fluctuating electromagnetic field outside a homogeneous material surface. The analysis is based on general results from the thermodynamics of irreversible processes, and requires no consideration of…
We study the Josephson effect in a clean Superconductor-Ferromagnet-Superconductor junction for arbitrarily large spin polarizations. The Andreev reflection at a clean Ferromagnet-Superconductor interface is incomplete, and Andreev channels…
We investigated the magnetotransport properties of mesoscopic platinum nanostructures (wires and rings) with sub-100 nm lateral dimensions at very low temperatures. Despite the strong spin-orbit interaction in platinum, oscillations of the…
The production of entangled pairs of electrons in ferromagnet-superconductor-ferromagnet or normal metal-superconductor-normal metal three-terminal structures has aroused considerable interest in the last twenty years. In these studies, the…
We propose a quantitative model for triplet superconductivity in Sr_2RuO_4 based on first principles calculations for the electronic structure and magnetic susceptibility. The superconductivity is due to ferromagnetic spin fluctuations,…
Multiband systems, which possess a wide parameter space, allow to explore a variety of competing ground states. Bright examples are the Fe-based pnictides and chalcogenides, which demonstrate metallic, superconducting, and various magnetic…
We have theoretically studied the temporal fluctuations and the resulting kinetic noise in the average spin polarization of an electron ensemble drifting in a quantum wire under a high electric field. Electrons are initially injected in the…
Fracton phases are a particularly exotic type of quantum spin liquids where the elementary quasiparticles are intrinsically immobile. These phases may be described by unconventional gauge theories known as tensor or multipolar gauge…
It has been shown that singlet Cooper pairs can be converted into triplet ones and diffuse into a ferromagnet over a long distance in a phenomenon known as the long-range proximity effect (LRPE). This happens in materials with inhomogeneous…
We discuss the spin fluctuations and the role played by the magnetic susceptibility in an atomic Fermi gas interacting with positive scattering length. Both thermal and quantum fluctuations are considered. Using a sum rule approach and…
Current fluctuations can provide additional insight into quantum transport in mesoscopic systems. The present work is carried out for the fluctuation properties of transport through a pair of coupled quantum dots which are connected with…
We investigate the formation and transport properties of chiral Andreev edge states in a two-dimensional quantum Hall system proximitized by a superconductor. By numerically modeling the system using the Bogoliubov-de Gennes equations, we…
We use the high sensitivity to magnetic flux of mesoscopic conductance fluctuations in large quantum dots to investigate changes in the two-dimensional electron dispersion caused by an in-plane magnetic field. In particular, changes in…
Spin and charge fluctuations and superconductivity in Na_0.35CoO_2*1.3H_2O are studied based on a multi-orbital Hubbard model. By applying the fluctuation exchange (FLEX) approximation, we show that the Hund's-rule coupling between the Co…
Andreev bound states are an expression of quantum coherence between particles and holes in hybrid structures composed of superconducting and non-superconducting metallic parts. Their spectrum carries important information on the nature of…
We find proximity-induced spontaneous spin and electric surface currents, at all temperatures below the superconducting T_c, in an isotropic s-wave superconductor deposited with a thin ferromagnetic metal layer with spin-orbit interaction.…
Molecular nanomagnets, besides promising to open new frontiers in technology, have attracted huge interest in the scientific community because they can exhibit the phenomenon known as quantum tunnelling of the magnetization, i.e. coherent…
We present a theory for a complete reconstruction of non-local spin correlations in ferromagnet-normal conductors. This quantum spin tomography is based on cross correlation measurements of electric currents into ferromagnetic terminals…
We present neutron scattering spectra taken from a single crystal of Na0.75CoO2, the precursor to a novel cobalt-oxide superconductor. The data contain a prominent inelastic signal at low energies (~10 meV), which is localized in wavevector…
The electron and hole states in a CdTe quantum dot containing a single magnetic impurity in an external magnetic field are investigated, using the multiband approximation which includes the heavy hole-light hole coupling effects. The…