Six-sublattice structure of the multiple-spin exchange model on the triangular lattice in the magnetic field

2H NMR spectra for D2O adsorbed on cellulose fibers which are macroscopically oriented demonstrate that the axis of cellulose fibers can be regarded as the director of the average molecular motion of the adsorbed D2O. The spectra for samples prepared from fiber sheets depend on the orientation of the sheets with respect to the magnetic field as well as the fiber orientation in the sheets. When the sheets are oriented perpendicular to the magnetic field, all the fibers in the sheets are perpendicular to the field irrespective of the fiber orientations in the sheets, and a partially overlapped quadrupole splitting is observed. When the sheets are oriented parallel to the magnetic field, the observed spectra deviate significantly from the expected 2D powder patterns, and the distribution of fiber orientations in the sheets has a significant influence on the observed band shape. An N-site mutual exchange model was used to account for the lateral diffusion of water molecules from one fiber to another. In a comparison of the simulated spectra based on the N-site mutual exchange model with the experimentally recorded spectra, the average lifetime for the adsorbed D2O molecules to reside on cellulose fibrils was estimated to be about 1.5 ms.

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A Design of Cesium Atomic Magnetometer Based on Circular Dichroism

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.203.268 ◽

2012 ◽

Vol 203 ◽

pp. 268-272 ◽

Cited By ~ 1

Author(s):

Xian Jin Zeng ◽

Mo Si Hao ◽

Qing Meng Li ◽

Qiang Liu ◽

Jun Hai Zhang ◽

...

Keyword(s):

Magnetic Field ◽

Circular Dichroism ◽

Spin Exchange ◽

Laser Light ◽

Tracking System ◽

Frequency Tracking ◽

Highly Sensitive ◽

Optical Configuration ◽

Circular Dichroïsm ◽

The Magnetic Field

Recently, atomic magnetometers have been reported as the most sensitive magnetometers by completely eliminating the spin exchange relaxation. In this paper, we described a design of highly sensitive cesium atomic magnetometer based on circular dichroism, which had the advantage of easily locking the probing laser to the necessary frequency compared with those based on circular birefringence. In order to polarize the cesium atoms uniformly, the pumping laser light was separated into two counter-propagating and counter-circular polarization beams through the atomic vapor cell. We employed a circular analyzer optical configuration to measure the ellipticity of the probing light, which indicated the amplitude of the magnetic field. The external magnetic field was tracked by a digital auto frequency tracking system.

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Electron transfer and spin exchange contributing to the magnetic field dependence of the primary photochemical reaction of bacterial photosynthesis

Biochimica et Biophysica Acta (BBA) - Bioenergetics ◽

10.1016/0005-2728(78)90047-6 ◽

1978 ◽

Vol 502 (2) ◽

pp. 255-268 ◽

Cited By ~ 95

Author(s):

Hans-Joachim Werner ◽

Klaus Schulten ◽

Albert Weller

Keyword(s):

Magnetic Field ◽

Electron Transfer ◽

Field Dependence ◽

Photochemical Reaction ◽

Magnetic Field Dependence ◽

Spin Exchange ◽

Bacterial Photosynthesis ◽

Primary Photochemical Reaction ◽

The Magnetic Field

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GROUND STATES OF A MIXTURE OF TWO SPECIES OF SPIN-1 BOSE GASES WITH INTERSPECIES SPIN EXCHANGE IN A MAGNETIC FIELD

International Journal of Modern Physics B ◽

10.1142/s0217979212500026 ◽

2012 ◽

Vol 26 (01) ◽

pp. 1250002 ◽

Cited By ~ 6

Author(s):

YU SHI ◽

LI GE

Keyword(s):

Magnetic Field ◽

Phase Diagram ◽

Phase Transitions ◽

Spin Exchange ◽

Quantum Phase Transitions ◽

Ground States ◽

Total Spin ◽

Quantum Phase ◽

Spin Coupling ◽

The Magnetic Field

We consider a mixture of two species of spin-1 atoms with both interspecies and intraspecies spin exchanges in a weak magnetic field. Under the usual single mode approximation, it can be reduced to a model of coupled giant spins. We find most of its ground states. This is a complicated problem of energy minimization, with three quantum variables under constraints, i.e., the total spin of each species and the total spin of the whole mixture, as well as four parameters, including intraspecies and interspecies spin coupling strengths and the magnetic field. The quantum phase diagram is very rich. Compared with the case without a magnetic field, the ground states are modified by a magnetic field, which also modifies the ground state boundaries or introduces new crossover regimes on the phase diagram. Without interspecies spin coupling, the quantum phase transitions existing in absence of a magnetic field disappear when a magnetic field is applied, which leads to crossover regimes in the phase diagram. Under ferromagnetic interspecies spin coupling, the ground states remain disentangled no matter whether there is a magnetic field. For antiferromagnetic interspecies spin coupling, a magnetic field entangles the ground states in some parameter regimes. When the intraspecies spin couplings are both ferromagnetic, the quantum phase transition between antiferromagnetic and zero interspecies spin couplings survives the magnetic field. When the intraspecies spin couplings are both antiferromagnetic, a magnetic field induces new quantum phase transitions between antiferromagnetic and zero interspecies spin couplings.

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