In usual experiments with BECs, the only relevant interaction is the isotropic and shortrange contact interaction, which is described by a single parameter, the scattering length a. In contrast, the dipole–dipole interaction between particles possessing an electric or magnetic dipole moment is of long range character and anisotropic, which gives rise to new phenomena 1. Most prominently, the st...

The thermodynamic properties of ferrofluids in applied magnetic fields are examined using theory and computer simulation. The dipolar hard sphere model is used. The second and third virial coefficients (B(2) and B(3)) are evaluated as functions of the dipolar coupling constant λ, and the Langevin parameter α. The formula for B(3) for a system in an applied field is different from that in the ze...

We study the ground states of rotating atomic Bose-Einstein condensates with dipolar interactions. We present the results of numerical studies on a periodic geometry which show vortex lattice ground states of various symmetries: triangular and square vortex lattices, “stripe crystal” and “bubble crystal”. We present the phase diagram (for systems with a large number of vortices) as a function o...

We demonstrate how dipolar interactions can have pronounced effects on the structure of vortices in atomic spinor Bose-Einstein condensates and illustrate generic physical principles that apply across dipolar spinor systems. We then find and analyze the cores of singular vortices with nonAbelian charges in the point-group symmetry of a spin-3 Cr condensate. Using a simpler model system, we anal...

Dipolar streamers are coronal structures formed by open solar flux converging from coronal holes of opposite polarity. Thus, the dipolar streamer belt traces the coronal foot point of the heliospheric current sheet, and it is strongly associated with the origin of slow solar wind. Pseudostreamers, on the other hand, separate converging regions of open solar flux from coronal holes of the same p...

Proton multipolar spin states associated with dipolar encoded longitudinal magnetization (DELM) and double-quantum (DQ) coherences of bound water are investigated for bovine and sheep Achilles tendon under mechanical load. DELM decay curves and DQ buildup and decay curves reveal changes of the 1H residual dipolar couplings for tendon at rest and under local compression forces. The multipolar sp...

A rotary resonance echo double resonance (R-REDOR) experiment is described for measuring heteronuclear dipolar coupling under magic-angle spinning. Rotary resonance reintroduces both dipolar coupling and chemical shift anisotropy with an rf field matching the spinning frequency. The resonance effect from chemical shift anisotropy can be refocused with a rotary resonance echo. The R-REDOR experi...

A technique for amplifying the apparent magnitudes of 13C-1H and 15N-1H dipolar interactions in magic-angle spinning experiments is described. By inserting rotor-synchronized 180 degrees pulses in the evolution period of a 2D dipolar-chemical shift experiment, heteronuclear dipolar couplings are doubled or quadrupled relative to the spinning speed. The increased number of dipolar sidebands is d...

Heteronuclear dipolar couplings of the protein backbone have proven to have a big impact on the accuracy of protein NMR structures. H,H dipolar couplings might have the same impact on side chains. Here we present a method that combines both heteronuclear and homonuclear dipolar couplings to investigate the local conformation of methylene groups. A new pulse sequence (SPITZE-HSQC) is presented, ...