English
Related papers

Related papers: Dipolar relaxation of cold sodium atoms in a magne…

200 papers

The thermally activated magnetic relaxation in two-dimensional ensembles of dipolar interacting nanoparticles with large uniaxial perpendicular anisotropy is studied by a numerical method and within the mean-field approximation. The role…

Condensed Matter · Physics 2009-11-10 S. I. Denisov , T. V. Lyutyy , K. N. Trohidou

We have investigated both theoretically and experimentally dipolar relaxation in a gas of magnetically trapped chromium atoms. We have found that the large magnetic moment of 6 $\mu_B$ results in an event rate coefficient for dipolar…

Quantum Physics · Physics 2009-11-10 S. Hensler , J. Werner , A. Griesmaier , P. O. Schmidt , A. Goerlitz , T. Pfau , S. Giovanazzi , K. Rzazewski

We study the magnetic relaxation of a system of localized spins interacting through weak dipole interactions, at a temperature large with respect to the ordering temperature but low with respect to the crystal field level splitting. The…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 A. Cuccoli , A. Fort , A. Rettori , E. Adam , J. Villain

We report a combined experimental and theoretical study of collision-induced dipolar relaxation in a cold spin-polarized gas of atomic nitrogen (N). We use buffer gas cooling to create trapped samples of 14N and 15N atoms with densities…

Atomic Physics · Physics 2011-03-07 T. V. Tscherbul , J. Klos , A. Dalgarno , B. Zygelman , Z. Pavlovic , M. T. Hummon , H-I Lu , E. Tsikata , J. M. Doyle

Magnetic atoms in a thin layer have repulsive interactions when their magnetic moments are aligned perpendicular to the layer. We show experimentally and theoretically how this can suppress dipolar relaxation, the dominant loss process in…

The relaxation time of weakly interacting classical spins is calculated by introducing the averages of the local dipolar field, obtained by thermodynamic perturbation theory, in a rigorous expression for the single-spin thermoactivation…

Materials Science · Physics 2009-11-07 P. E. Jönsson , J. L. Garcia-Palacios

We investigate the spin relaxation induced by acoustic phonons in the presence of spin-orbit interactions in single electron Si/SiGe lateral coupled quantum dots. The relaxation rates are computed numerically in single and double quantum…

Mesoscale and Nanoscale Physics · Physics 2015-03-17 Martin Raith , Peter Stano , Jaroslav Fabian

Highly accurate numerical results of phonon-induced two-electron spin relaxation in silicon double quantum dots are presented. The relaxation, enabled by spin-orbit coupling and the nuclei of $^{29}$Si (natural or purified abundance), are…

Mesoscale and Nanoscale Physics · Physics 2013-02-01 Martin Raith , Peter Stano , Jaroslav Fabian

Inelastic spin relaxation and spin splitting $\epsilon_{\mathrm{s}}$ in lateral quantum dots are studied in the regime of strong in-plane magnetic field. Due to both g-factor energy dependence and spin-orbit coupling $\epsilon_{\mathrm{s}}$…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Vladimir I. Fal'ko , B. L. Altshuler , O. Tsyplyatev

We employ the method of the theory of open quantum systems to analyze spin relaxation and decoherence in semiconductors in the presence of a magnetic field. We derive a set of Bloch equations for electron spin with a fully microscopic…

Condensed Matter · Physics 2007-05-23 Vadim I. Puller , Lev G. Mourokh , Norman J. M. Horing , Anatoly Yu. Smirnov

The longitudinal dipole response of a quantum dot has been calculated in the far-infrared regime using local spin density functional theory. We have studied the coupling between the collective spin and density modes as a function of the…

Condensed Matter · Physics 2009-10-31 Ll. Serra , M. Barranco , A. Emperador , M. Pi , E. Lipparini

Using the two-level approximation of the energy barrier, we perform extensive kinetic Monte Carlo simulations to probe the relaxation characteristics in a two-dimensional ($L^{}_x\times L^{}_y$) array of magnetic nanoparticle as a function…

Materials Science · Physics 2022-03-23 Manish Anand

The prospects of sympathetic cooling of polar molecules with magnetically co-trapped alkali-metal atoms are generally considered poor due to strongly anisotropic atom-molecule interactions leading to large spin relaxation rates. Using…

Atomic Physics · Physics 2012-02-06 T. V. Tscherbul , J. Klos , A. A. Buchachenko

We explore the quantum dynamics of nuclear spin relaxation in cold collisions of $^1\Sigma^+$ molecules with structureless atoms in an external magnetic field. To this end, we develop a rigorous coupled-channel methodology, which accounts…

Chemical Physics · Physics 2023-06-29 Rebekah Hermsmeier , Xiaodong Xing , Timur V. Tscherbul

The magnetic relaxation and hysteresis of a system of single domain particles with dipolar interactions are studied by Monte Carlo simulations. We model the system by a chain of Heisenberg classical spins with randomly oriented easy-axis…

Materials Science · Physics 2007-05-23 Oscar Iglesias , Amilcar Labarta

We study the effect of a magnetic field on the thermal relaxation of non-interacting small monodomain particle systems particles with a distribution of anisotropy constants and random easy-axes directions. Numerical calculations of the…

Materials Science · Physics 2007-05-23 Oscar Iglesias , Amilcar Labarta

The physical properties of magnetic nanoparticles have been investigated with focus on the influence of dipolar interparticle interaction. For weakly coupled nanoparticles, thermodynamic perturbation theory is employed to derive analytical…

Materials Science · Physics 2016-08-31 Petra E. Jönsson

We study dipolar relaxation in both ultra-cold thermal and Bose-condensed chromium atom gases. We show three different ways to control dipolar relaxation, making use of either a static magnetic field, an oscillatory magnetic field, or an…

At temperatures below the magnetic anisotropy energy, monodomain magnetic systems (small particles, nanomagnetic devices, etc.) must relax quantum mechanically. This quantum relaxation must be mediated by the coupling to both nuclear spins…

Condensed Matter · Physics 2009-10-28 N. V. Prokof'ev , P. C. E. Stamp

We study spin wave excitations in a three-dimensional nanocomposite magnet of exchange coupled hard (SmCo$_5$) and soft (FeCo) phases. The dipolar interaction splits the spin wave energies into the upper and lower branches of the spin wave…

Materials Science · Physics 2017-04-05 A. M. Belemuk , S. T. Chui
‹ Prev 1 2 3 10 Next ›