For a long time, it has been generally believed that spin-spin interactions can only exist in a theory where Lorentz symmetry is gauged, and a theory with spin-spin interactions is not perturbatively renormalizable. B...For a long time, it has been generally believed that spin-spin interactions can only exist in a theory where Lorentz symmetry is gauged, and a theory with spin-spin interactions is not perturbatively renormalizable. But this is not true. By studying the motion of a spinning particle in gravitational field, it is found that there exist spin-spin interactions in gauge theory of gravity. Its mechanism is that a spinning particle will generate gravitomagnetic field in space-time, and this gravitomagnetic field will interact with the spin of another particle, which will cause spin-spin interactions. So, spin-spin interactions are transmitted by gravitational field. The form of spin-spin interactions in post Newtonian approximations is deduced. This result can also be deduced from the Papapetrou equation. This kind of interaction will not affect the renormalizability of the theory. The spin-spin interactions will violate the weak equivalence principle, and the violation effects are detectable. An experiment is proposed to detect the effects of the violation of the weak equivalence principle.展开更多
The spin-spin coupling can provide useful information for analysing the structure of a system and the extent of non-covalent bonds interactions.In this study,we present the isotropic NMR properties and spinspin coupli...The spin-spin coupling can provide useful information for analysing the structure of a system and the extent of non-covalent bonds interactions.In this study,we present the isotropic NMR properties and spinspin coupling involving ruthenium-ligand(Ru-L)bonds and other spin-spin interactions obtained from DFT calculations.The proton shift which in close proximity with the Ru and Cl(or O)atoms are characterised with lower and higher chemical shift respectively.Though Ru-Cl bond has longer bond length than all other Ru-L bonds,yet its spin-spin coupling is higher than others because of a very high contribution of PSO which is far higher than the contribution from FC terms.In all other Ru-L bonds,FC is the most significant Ramsey terms that define their spin-spin coupling.Both the isotropic and anisotropic shielding of the Hz of the pyrazole is lower than Hc of the cymene and the spin-spin coupling 3J(Hz…Hz)of the pyrazole are less than half of the 3J(Hc…Hc)of the cymene unit in the complexes.There is a little increase in both the 3J(Hc…Hc)and 3J(Hz…Hz)spin-spin coupling in the hydrolysed complexes compare to the non-hydrolysed complexes.The isotropic and anisotropic shielding tensor of Ru atoms increases in magnitude as the complexes get hydrolysed that could be ascribed to a more deshielding chemical environments.展开更多
The effects of spin-spin interaction on thermed entanglement of a two-qubit Heisenberg XYZ model with different inhomogeneous magnetic fields are investigated. It is shown that the entanglement is dependent on the spi...The effects of spin-spin interaction on thermed entanglement of a two-qubit Heisenberg XYZ model with different inhomogeneous magnetic fields are investigated. It is shown that the entanglement is dependent on the spin-spin interaction and the inhomogeneous magnetic fields. The larger the Ji (i-axis spin-spin interaction), the higher critical value the Bi (i-axis uniform magnetic field) has. Moreover, in the weak-field regime, the larger Ji corresponds to more entanglement, while in the strong-field regime, different Ji correspond to the same entanglement. In addition, it is found that with the increase of Ji, the concurrence can approach the maximum value more rapidly for the smaller Bi, and can reach a larger value for the smaller bi (i-axis nonuniform magnetic field). So we can get more entanglement by increasing the spin-spin interaction Ji, or by decreasing the uniform magnetic field Bi and the nonuniform magnetic field hi.展开更多
NMR relaxometry is one of the techniques that allow observing changes in the molecular mobility that come from materials’ morphology. T1H has been used to monitor food and polymer sciences. However, T2>H, although...NMR relaxometry is one of the techniques that allow observing changes in the molecular mobility that come from materials’ morphology. T1H has been used to monitor food and polymer sciences. However, T2>H, although being a revealing as T1>H, is rarely used to analyze changes in thermoplastic systems it is more sensitive to the mobile region. High Impact Polystyrene nanomaterials were prepared through solution casting and were exposed for different times to UV light in the air. The samples, removed after each exposure interval, were characterized by T2>H, focusing on the changes in the relaxation data. The results for this parameter showed that the changes in the relaxation data come from the competition of chain scission and chain recombination processes, which occurs due to the UV light influence with increased time. The T2>H data indicated that the clay ratio can influence the chain degradation processes, acting to inhibit or accelerate the aging process [1] [2].展开更多
In this work we present a model for the determination of the interaction energy for triplet and singlet states in atoms with incomplete filled shells. Our model includes the modification of the Coulomb’s law by the i...In this work we present a model for the determination of the interaction energy for triplet and singlet states in atoms with incomplete filled shells. Our model includes the modification of the Coulomb’s law by the interaction between the magnetic moments of the electrons. We find that the energy of the triplet state is lower than the energy of the singlet state. We calculate the interaction energy between the electrons from the adjacent atoms in fcc lattices and we find that the minimum interaction energy is attained for the triplet state. The result is presented for the interaction between the electrons of the first coordination group and those of the second coordination group. The interaction energy which aligns the spins is used to evaluate the Curie temperature in a mean field model.展开更多
The present model deals with a protocol which involves the generation and conversion of entanglement from pathspin(P-S)hybrid entanglement associated with half-spin particle to spin-spin(S-S)interparticle entanglement...The present model deals with a protocol which involves the generation and conversion of entanglement from pathspin(P-S)hybrid entanglement associated with half-spin particle to spin-spin(S-S)interparticle entanglement.This protocol finds its applications in quantum information processing via a series of operations which include a beam splitter,spin flipper,spin measurement,classical channel,unitary transformations.Finally,it leads to two particles having completely entangled spin variables,without any requirement of any simultaneous operation on the two particles.展开更多
文摘For a long time, it has been generally believed that spin-spin interactions can only exist in a theory where Lorentz symmetry is gauged, and a theory with spin-spin interactions is not perturbatively renormalizable. But this is not true. By studying the motion of a spinning particle in gravitational field, it is found that there exist spin-spin interactions in gauge theory of gravity. Its mechanism is that a spinning particle will generate gravitomagnetic field in space-time, and this gravitomagnetic field will interact with the spin of another particle, which will cause spin-spin interactions. So, spin-spin interactions are transmitted by gravitational field. The form of spin-spin interactions in post Newtonian approximations is deduced. This result can also be deduced from the Papapetrou equation. This kind of interaction will not affect the renormalizability of the theory. The spin-spin interactions will violate the weak equivalence principle, and the violation effects are detectable. An experiment is proposed to detect the effects of the violation of the weak equivalence principle.
基金financial support of Govan Mbeki Research and Development Centre,University of Fort Hare,South Africa
文摘The spin-spin coupling can provide useful information for analysing the structure of a system and the extent of non-covalent bonds interactions.In this study,we present the isotropic NMR properties and spinspin coupling involving ruthenium-ligand(Ru-L)bonds and other spin-spin interactions obtained from DFT calculations.The proton shift which in close proximity with the Ru and Cl(or O)atoms are characterised with lower and higher chemical shift respectively.Though Ru-Cl bond has longer bond length than all other Ru-L bonds,yet its spin-spin coupling is higher than others because of a very high contribution of PSO which is far higher than the contribution from FC terms.In all other Ru-L bonds,FC is the most significant Ramsey terms that define their spin-spin coupling.Both the isotropic and anisotropic shielding of the Hz of the pyrazole is lower than Hc of the cymene and the spin-spin coupling 3J(Hz…Hz)of the pyrazole are less than half of the 3J(Hc…Hc)of the cymene unit in the complexes.There is a little increase in both the 3J(Hc…Hc)and 3J(Hz…Hz)spin-spin coupling in the hydrolysed complexes compare to the non-hydrolysed complexes.The isotropic and anisotropic shielding tensor of Ru atoms increases in magnitude as the complexes get hydrolysed that could be ascribed to a more deshielding chemical environments.
基金Supported by National Natural Science Foundation of China under Grant No. 10704001Anhui Provincial Natural Science Foundation under Grant No. 070412060+1 种基金the Major Program of the Education Department of Anhui Province under Grant No. KJ2010ZD08the Key Program of the Education Department of Anhui Province under Grant No. KJ2010A287
文摘The effects of spin-spin interaction on thermed entanglement of a two-qubit Heisenberg XYZ model with different inhomogeneous magnetic fields are investigated. It is shown that the entanglement is dependent on the spin-spin interaction and the inhomogeneous magnetic fields. The larger the Ji (i-axis spin-spin interaction), the higher critical value the Bi (i-axis uniform magnetic field) has. Moreover, in the weak-field regime, the larger Ji corresponds to more entanglement, while in the strong-field regime, different Ji correspond to the same entanglement. In addition, it is found that with the increase of Ji, the concurrence can approach the maximum value more rapidly for the smaller Bi, and can reach a larger value for the smaller bi (i-axis nonuniform magnetic field). So we can get more entanglement by increasing the spin-spin interaction Ji, or by decreasing the uniform magnetic field Bi and the nonuniform magnetic field hi.
文摘NMR relaxometry is one of the techniques that allow observing changes in the molecular mobility that come from materials’ morphology. T1H has been used to monitor food and polymer sciences. However, T2>H, although being a revealing as T1>H, is rarely used to analyze changes in thermoplastic systems it is more sensitive to the mobile region. High Impact Polystyrene nanomaterials were prepared through solution casting and were exposed for different times to UV light in the air. The samples, removed after each exposure interval, were characterized by T2>H, focusing on the changes in the relaxation data. The results for this parameter showed that the changes in the relaxation data come from the competition of chain scission and chain recombination processes, which occurs due to the UV light influence with increased time. The T2>H data indicated that the clay ratio can influence the chain degradation processes, acting to inhibit or accelerate the aging process [1] [2].
文摘In this work we present a model for the determination of the interaction energy for triplet and singlet states in atoms with incomplete filled shells. Our model includes the modification of the Coulomb’s law by the interaction between the magnetic moments of the electrons. We find that the energy of the triplet state is lower than the energy of the singlet state. We calculate the interaction energy between the electrons from the adjacent atoms in fcc lattices and we find that the minimum interaction energy is attained for the triplet state. The result is presented for the interaction between the electrons of the first coordination group and those of the second coordination group. The interaction energy which aligns the spins is used to evaluate the Curie temperature in a mean field model.
文摘The present model deals with a protocol which involves the generation and conversion of entanglement from pathspin(P-S)hybrid entanglement associated with half-spin particle to spin-spin(S-S)interparticle entanglement.This protocol finds its applications in quantum information processing via a series of operations which include a beam splitter,spin flipper,spin measurement,classical channel,unitary transformations.Finally,it leads to two particles having completely entangled spin variables,without any requirement of any simultaneous operation on the two particles.