相关论文: Dielectric relaxation by quantum critical magnons

Magnetic resonance is a prime method for the study of chemical and biological structures and their dynamical processes. The interpretation of these experiments relies on considering the spin of electrons as the sole relevant degree of…

By extending our recently proposed magnon-density-waves to low dimensions, we investigate, using a microscopic many-body approach, the longitudinal excitations of the quasi-one-dimensional (quasi-1d) and quasi-2d Heisenberg…

Ultracold dipolar particles pinned in optical lattices or tweezers provide an excellent platform for studying out-of-equilibrium quantum magnetism with dipole-mediated couplings. Starting with an initial state with spins of opposite…

Lattice dynamics and magnetic excitations are investigated to elucidate the origin of magneto-dielectric effects in the S=1/2 two-dimensional quantum spin compound K$_2$V$_3$O$_8$. We find evidence for lattice instabilities at 110 K and 60…

For the first time, magnetization of high-Tc samples with different crystalline structure and its isothermal relaxation is studied at very weak constant fields (H <= 0.1 Oe) for temperatures close to the critical ones. Essential influence…

In two previous papers we studied the problem of electronic properties in a system with long-ranged helimagnetic order caused by itinerant electrons. A standard many-fermion formalism was used. The calculations were quite tedious because…

The quasiparticle density of states in correlated and quantum-critical metals directly probes the effect of electronic correlations on the Fermi surface. Measurements of the nuclear spin-lattice relaxation rate provide one such experimental…

We present a detailed dielectric study of the relaxation effects that occur in several perovskite rare-earth manganites, including the multiferroics TbMnO3 and DyMnO3. We demonstrate that the strong magnetocapacitive effects, observed for…

We extend recently proposed variational coupled-cluster method to describe excitation states of quantum antiferromagnetic bipartite lattices. We reproduce the spin-wave excitations (i.e., magnons with spin $\pm 1$). In addition, we obtain a…

We report Knight shift experiments on the superconducting heavy electron material CeCoIn$_5$ that allow one to track with some precision the behavior of the heavy electron Kondo liquid in the superconducting state with results in agreement…

Electron spin relaxation in a spin-polarized quantum Hall state is studied. Long spin relaxation times that are at least an order of magnitude longer than those measured in previous experiments were observed and explained within the…

A thorough investigation of the relaxational dynamics in the recently discovered multiferroic CdCr2S4 showing a colossal magnetocapacitive effect has been performed. Broadband dielectric measurements without and with external magnetic…

Muon spin relaxation experiments have been performed in the pyrochlore iridate Pr_2Ir_2O_7 for temperatures in the range 0.025-250 K. Kubo-Toyabe relaxation functions are observed up to > 200 K, indicating static magnetism over this…

We have investigated spin relaxation times in CdTe quantum dots doped with a single Mn atom, a prototype of a system where the interaction between a single charge carrier and a single spin takes place. A theoretical model that was used…

We directly measure the low energy excitation modes of the quantum Ising magnet LiHoF$_4$ using microwave spectroscopy. Instead of a single electronic mode, we find a set of collective electronuclear modes, in which the spin-$1/2$ Ising…

We have studied spin relaxation in the spin ice compound Dy2Ti2O7 through measurements of the a.c. magnetic susceptibility. While the characteristic spin relaxation time is thermally activated at high temperatures, it becomes almost…

Dielectric study over a broadband was carried out from 10 to 70 K on ceramic Gd1-xYxMnO3 (x= 0.2, 0.3, and 0.4). For all the compositions, a prominent sharp peak about ~18K was observed in the temperature dependence of both {\epsilon}'(T)…

Magneto-acoustic investigations of the frustrated triangular-lattice antiferromagnet Cs2CuCl4 were performed for the longitudinal modes c11 and c33 in magnetic fields along the a-axis. The temperature dependence of the sound velocity at…

We theoretically study the relaxation of electron orbital states of a double quantum dot system due to two-phonon processes. In particular, we calculate how the relaxation rates depend on the separation distance between the quantum dots,…

An experimental technique for the indirect manipulation and detection of electron spins entangled in two-dimensional magnetoexcitons has been developed. The kinetics of the spin relaxation has been investigated. Photoexcited…