The JA-SW hybrid model is extended in order to include the strain or stress anisotropy. With this improved model, a simulation is carried out to study the effects of stress on magnetic hysteresis loss and coercivity of ferromagnetic film. It is shown that the hysteresis loss and coercivity are related to the external field orientation, the stress intensity and the stress direction. Hysteresis loss, or the coercive force does not entirely monotonially increase with the change of stress intensity. For example, when the external field is parallel to the easy axis, a valley appears in the curve. In addition, stress will cause the peak offset of the coercivity curve as the orientation angle of the external field changes. Extensive comparisons of results with literature data are made and the differences between them are explained.

This paper is devoted to the study of electronic and phonon spectra of a kind of generalized Fibonacci quasiperiodic chain (Twins model). Renormalization group results show that the electronic spectrum has a trifurcating selfs milar structure but the middle subbends in every hierarchy are similar to spetral structure of the periodic systems. The analysis is confirmed by numerical results. While the phoson spectrum shows the same spectral structure as that of the Fibonacci chain.

By using the measure of concurrence, the entanglement of the ground state in the one-dimensional Anderson model is studied with consideration of the long-range correlations. Three kinds of correlations are discussed. We compare the effects of the long-rang Gaussian and power-law correlations between the site energies on the concurrence, and demonstrate the existence of the band structure of the concurrence in the power-law case. The emergence of the sharp kink on the concurrence curve shown in the intraband or in the interband indicates the position at which the localization extent of the state may have the severe variation. We use the Rudin-Shapiro model to describe the site energy distribution of the nucleotides of the DNA chain: guanine (G), adenine (A), cytosine(C), thymine (T). This model is a tetradic quasiperiodic sequence and is shown to be long-range correlated. Our results show that correlations between the site energies increase the concurrences.

Excessive spin-torque critical current has long been a problem received much attention. In this paper, we suggest that by introducing the out-of-plane stress or the stress anisotropy field, the out-of-plane demagnetizing field can be compensated effectively, and in this way the spin-torque critical current can be reduced. Specifically, the four-component distributed spin-circuit model is used to calculate the polarization current which is transferred from the polarizer to the detector (free layer).The properties of magnetization switching in the free layer of the lateral spin valve are studied under the influence of stress by using the Landau-Lifshitz-Gilbert-Slonczewski (LLGS) equation. Results show that, if the stress direction is appropriately selected, the out-of-plane demagnetizing field can be effectively compensated, thereby the spin torque critical current can be significantly reduced. Furthermore, as the stress is increased and the demagnetizing field is reduced, the magnetization reversal time is greatly reduced.

The temperature stability of the quantum magnetic disk constructed on a triangular manowire array is studied by the damage spreading method. Three aspects are considered in order to make the Ising model more realistic. Firstly, we include the long-range interaction between spins. Secondly, we take into account the disorder of the nanowire lengths. At last, we present an estimation of the spin interaction constant through the system coercive force by deriving the relation between the spin interaction constant and the coercive force. It is shown that the longer the spin interaction acts, the more stable the system becomes. On the other hand, the system has greater temperature instability when the disorder degree of the nanowire lengths is increased.