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In the field of ultrafast magnetism, i.e., subpicosecond or femtosecond time scales, the dynamics of magnetization can be described by the inertial Landau-Lifhitz-Gilbert equation. In terms of this equation, the intrinsic characteristics is investigated in detail for the theoretical limit of the magnetization reversal field. We can find that there is a critical value for the inertia parameter τc , which is affected by the damping and anisotropy parameter of the system. When the inertial parameter factor τ < τc , the limit value of the magnetization reversal field under the ultrafast magnetic mechanism is less than that of the fast magnetic mechanism. When τ > τc , the limit value of the magnetization reversal field will be greater than the limit value under the fast magnetic mechanism. Moreover, it is important to point out that the limit value of the magnetization reversal field under the ultrafast magnetic mechanism decreases with the increasing inertial factor, as τ < τc /2, while increases with inertial factor τ as τ > τc /2. Finally, with the joint action of damping and anisotropy, compared with fast magnetism, we find that the limit value of the magnetization reversal field has rich variation characteristics, i.e., there is not only a linear and proportional relationship, but also an inverse relationship, which is very significant for the study of ultrafast magnetism.

Two-dimensional (2D) material-based van der Waals heterostructures (vdWHs) have been identified as an excellent platform from which to expand various device applications for light-emitting, photovoltaic, and field-effect transistors because of their different band alignments, including type-I, type-II, and type-III. However, it is difficult to achieve transformations between types of band alignment in a single heterostructure for diverse applications. In this study, the effects of a vertical electric field on the band alignment transition and electronic properties of 2D ${\rm{GaSe}}/{\rm{SnS}}_{2}$ (${\rm{SnSe}}_{2}$) vdWHs are investigated systematically using density functional theory calculations. The study shows that the electric field can modulate not only the band gap but also the band alignment to produce multifunctional device applications. A positive electric field can control the band alignment transformation from type-II to type-I for electric field values of approximately 0.39 V/\AA{} (0.12 V/\AA{}), while a negative electric field can transform the type-II to type-III band alignments for electric field values of about \ensuremath{-}0.2 V/\AA{} (\ensuremath{-}0.16 V/\AA{}) in ${\rm{GaSe}}/{\rm{SnS}}_{2}$ (${\rm{SnSe}}_{2}$) vdWHs. We trace these surprising results to the conduction band and valence band edge position movements for the linear decrease of ${\rm{GaSe}}$, while the linear increase of ${\rm{SnS}}_{2}$ (${\rm{SnSe}}_{2}$) occurs with the applied electric field. The present work may provide a direction for tunable multiple-band alignments in 2D vdWHs and help achieve multifunctional device applications.

Today East Asia harbors many “relict” plant species whose ranges were much larger during the Paleogene-Neogene and earlier. The ecological and climatic conditions suitable for these relict species have not been identified. Here, we map the abundance and distribution patterns of relict species, showing high abundance in the humid subtropical/warm-temperate forest regions. We further use Ecological Niche Modeling to show that these patterns align with maps of climate refugia, and we predict species’ chances of persistence given the future climatic changes expected for East Asia. By 2070, potentially suitable areas with high richness of relict species will decrease, although the areas as a whole will probably expand. We identify areas in southwestern China and northern Vietnam as long-term climatically stable refugia likely to preserve ancient lineages, highlighting areas that could be prioritized for conservation of such species., We acknowledge funding by the Global Environmental Research (S-14) of the Ministry of the Environment (Japan), the Proyecto Intramural Especial, PIE (grant no. 201630I024) from the CSIC, Spain, the Natural Science Foundation Project of CQ CSTC (cstc2016jcyjA0379) (China), and the Northeastern Research Institute of Petrified Wood and Mineral Resources, Nakhon Ratchasima Rajabhat University (Thailand).

Recently, all-inorganic two-dimensional (2D) Ruddlesden-Popper (RP) halide perovskites have drawn much attention due to their excellent stability in ambient air. However, their electronic and optical performance resulting from a wide bandgap and low carrier mobility have hindered their use in photodetectors. To overcome these limitations, in this work, taking advantage of hexagonal indium selenide ($\mathrm{In}\mathrm{Se}$) with a high electron mobility, we construct an atomically thin heterostructure. Density-functional-theory (DFT) calculations of the electronic and optical properties are performed for these heterostructures. The results demonstrate that the photodetection response spectrum of the heterostructures is significantly broadened as the bandgap decreases from 2.17 to 0.40 eV for the $\mathrm{In}\mathrm{Se}$/${\mathrm{Cs}}_{2}{\mathrm{Sn}\mathrm{I}}_{2}{\mathrm{Cl}}_{2}$ heterostructure. Moreover, the electron effective mass, ${m}_{e}^{\ensuremath{\ast}}$, is reduced from 1.13 ${m}_{0}$ to 0.41 ${m}_{0}$ for the $\mathrm{In}\mathrm{Se}$/${\mathrm{Cs}}_{2}{\mathrm{Ge}\mathrm{I}}_{2}{\mathrm{Cl}}_{2}$ heterostructure. The significant reductions in both the band gap and effective mass are determined to be related to the type-II band alignment, which favors the carrier separation at the interface. The physical mechanisms related to the usage of this material in photodetectors are also discussed. The proposed III--VI semiconductor InSe and all-inorganic 2D RP perovskite ${\mathrm{Cs}}_{2}X{\mathrm{I}}_{2}{\mathrm{Cl}}_{2}$ (X = $\mathrm{Pb}$, $\mathrm{Sn}$, and $\mathrm{Ge}$) heterostructures provide challenges and opportunities for designing high-performance photodetectors.

We theoretically investigate the Dzyaloshinskii–Moriya solitons driven by the magnetic field and spin-polarized current in anisotropic ferromagnetic nanowires. The external field and Dzyaloshinskii–Moriya interaction determine the formation region of soliton solution and the corresponding phase diagram is given for different types of solitons. The Dzyaloshinskii–Moriya interaction affects the internal structure distortion of solitons which determines the soliton energy. Also, we obtain the critical value of Dzyaloshinskii–Moriya interaction for soliton formation. The roles of Dzyaloshinskii–Moriya interaction effect on the soliton energy are completely opposite for the solitons of type I and type II in ferromagnetic nanowires.

We investigate the spin-related currents and tunnel magnetoresistance through a quantum dot, which is side-coupled with a Majorana fermion zero mode and two thermal-driven ferromagnetic electrodes. It is found that the interplay of Majorana fermion and electrodes’ spin polarization can induce a nonlinear thermal-bias spin current. This interplay also decreases the total magnitude of spin or charge current, in either parallel or antiparallel configuration. In addition, a thermal-driven negative tunnel magnetoresistance is found, which is an unique feature to characterize Majorana fermion. With large temperature difference, a step phenomenon is observed in gate tuned spin-up current. When the coupling between quantum dot and topological superconductor is strong enough, this step will evolve into a linear relation, revealing Majorana fermion’s robustness.

In quantum transport, especially in spintronics, its central theme is to manipulate spin degrees of freedom in solid-state systems, to understand the interaction between the particle spin and its solid-state environments and to make useful devices. Recently, Majorana fermion has been introduced into quantum transport and received much attention. In this paper, we study a thermal-driven transport model which consists of a quantum dot coupled with two normal metal leads, a impurity spin (whose angular quantum number is more than or equal to one-half) and a Majorana fermion. We focus on the interplay between Majorana fermion and the impurity in this exactly solvable model. It is found that the system can generate thermal-induced spin current, and the currents are affected by Majorana fermion and impurity. With large temperature difference, the currents are sensitive to gate voltage, and the quantitative relation between spin-up current and gate voltage tends to be linear when the coupling between Majorana and quantum dot is strong, showing Majorana fermion's robustness. In addition, the spin current induced by Majorana fermion exhibits an oscillating antisymmetric structure around zero-bias point. This spin current’s zero point is related to the angular quantum number of impurity spin. These results are expected to be useful in thermal-electric conversion devices, and may be observed in future experiments.

We investigated the anharmonic effects on the dynamics and measurement accuracy of a multimode cold atomic interferometer driven by two Kapitza–Dirac pulses. The first Kapitza–Dirac pulse creates several spatially addressable modes from the ground state of an anharmonic trap and the external field. These modes evolve along different paths and coherently recombine under the anharmonic potential. The second Kapitza–Dirac pulse separates these mixed modes again. The anharmonic effect causes the asymmetry of the density distribution function of the cold atoms and it is observed at the measurement time. The expected sensitivity is calculated by the Fisher information and the Cramer–Rao lower bound. As the anharmonic effect is enhanced, the measurement accuracy of the current atomic interferometer is slightly reduced relative to the measurement accuracy Δ g ∕ g ≈ 1 0 − 9 in the case of a harmonic trap.

Based on the uniform, helical and spiral domain-wall magnetic configurations, the excited spin waves are studied with emphasis on the role of damping. We find that the damping closes the gap of dispersion, and greatly influences the dispersion in the long-wave region for the spin waves of spiral wall and helical structure. For the uniform configuration, the Dzyaloshinskii–Moriya interaction determines the modification of dispersion by the damping. Furthermore, we investigate the interaction between spin waves and a moving spiral domain wall. In the presence of damping, the amplitude of spin wave can increase after running across the wall for small wave numbers. Driving by the spin waves, the wall propagates towards the spin-wave source with an increasing velocity. Unlike the case without damping, the relation between the wall velocity and the spin-wave frequency depends on the position of wall.

In the original version of this Article, an incorrect sample size was provided for the number of relict species (443 instead of 442) and the number of relict forests (423 instead of 422). These errors have been corrected in both the PDF and HTML versions of the Article.

A theoretical study is presented on the dynamics of polaritons in semiconductor microcavities near parametric instability thresholds. With upward or downward ramp of optical pump, different instability modes emerge in parameter space defined by damping and detuning. According to these modes, stationary short-wave, stationary periodic, oscillatory periodic, and oscillatory uniform parametric instabilities are distinguished. By multiple scale expansion, the dynamics near threshold can be described by a critical mode with a slowly varying amplitude for the last three instabilities. Furthermore, it is found that the evolutions of their amplitudes are governed by real or complex Ginzburg–Landau equations.

We extend the Green function approach to quantum transport through an anisotropic molecular magnet system with the help of Hubbard operators. Based on the single molecular magnet model, we reformulate the large spin and the total Hamiltonian in the language of Hubbard operators and obtain analytical expressions of the retarded Green function in sequential tunneling and Kondo regimes. In addition to this, we show the connection of our method to the master equation method in sequential regime and discuss a simple isotropic case in Kondo regime, in which we find a three-peak Kondo structure, a feature characterizing the isotropic exchange interaction between the localized electron and large spin.

Multiferroic composites possess the coupling effect among mechanical, electrical, and magnetic ordering, showing potential applications in compact, fast, and low-power magnetoelectric devices. Owing to the increasing application demand, the researches of device design, micro-/nano-fabrication, and performance test of magnetoelectric devices have made continuous progress. In this review, we briefly introduce several prototype devices based on magnetoelectric coupling, analyze the noteworthy application techniques, and summarize the working mechanisms and performances of devices including tunable inductors, RF/microwave filters, magnetoelectric memories, energy harvesters, magnetoelectric sensors, magnetoelectric antennas, etc. Besides, we discuss the issues and challenges in researches of multiferroic magnetoelectric devices, and present the perspectives for improving the device performance.

In this paper, the higher nonlinear Schrödinger equation is solved by the Hirota method. As an example, the exact grey one- and two-soliton solutions in explicit forms are generated analytically under the continuous-wave background. The results reveal that the velocity of the grey soliton is clearly affected by the higher order effects, yet the grey soliton propagates without any change in their shape and intensity. The higher order term and the phase velocity play the important role for the maximum valley of grey soliton, i.e., the intensity of grey soliton. For the black soliton, the velocity of soliton is determined only by the higher order effects. The analysis of the asymptotic behavior of a two grey soliton solution shows the collision is elastic.

We study the interaction of a nonlinear spin-wave and magnetic soliton in a uniaxial anisotropic ferromagnet. By means of a reasonable assumption and a straightforward Darboux transformation one- and two-soliton solutions in a nonlinear spin-wave background are obtained analytically, and their properties are discussed in detail. In the background of a nonlinear spin wave the amplitude of the envelope soliton has the spatial and temporal period, and soliton can be trapped only in space. The amplitude and wave number of spin wave have the different contribution to the width, velocity, and the amplitude of soliton solutions, respectively. The envelope of solution hold the shape of soliton, and the amplitude of each envelope soliton keeps invariability before and after collision which shows the elastic collision of two envelope soliton in the background of a nonlinear spin wave.

To estimate the apex field enhancement factor associated with carbon nanotube on a planar cathode surface, the simple model of floated sphere between parallel anode and cathode plates was studied. When the anode-cathode distance d is much larger than the height h of carbon nanotube, the field enhancement factor of carbon nanotube was given as the following expression β0=h∕ρ+3.5 with the image method, which is a little than the early work of Miller. Finally, the influence of the anode-cathode distance on the enhancement factor was also discussed and the expression of enhancement factor of carbon nanotube should be modified to be β=h∕ρ+3.5+A(h∕d)3, where A is the constant. This shows a much weaker influence of the relatively smaller anode-cathode distance on the field enhancement factor of carbon nanotube than that estimated earlier. Thus, we can lower the threshold voltage to some extent by the decrease of the anode-cathode distance. The higher aspect ratio of carbon nanotube and the lower anode-cathode di...

The effects of annealing temperature on TbFe films prepared by dc magnetron sputtering were discussed. X-ray diffraction patterns indicate that these polycrystalline films consisting mainly of α-Fe and TbFe2 lave phase with grain sizes less than 25 nm can be obtained by a rapid cycle annealing process. Grain sizes can be controlled by varying annealing temperatures. Film hysteresis loop studies show that annealing treatment can improve TbFe film in-plane soft magnetic performances. Magnetic domain structures explored by a magnetic force microscopy show that in the as-deposited films, maze domain structures exist, hence it possesses perpendicular anisotropy and larger anisotropic constant Ku. No domains are observed when annealing temperature is lower than 400 degrees C. However, maze domain structures appear again when annealing temperature is higher than 400 degrees C. Two maxima of magnetostrictive coefficients are obtained at annealing temperatures of 300 degrees C and 500 degrees C in the presence of a 40 kA.m−1 external magnetic field.

For the Bariev model with single electron hopping, pair hopping and hard core potential, we prove the integrability of this model under open boundary conditions and obtained the Bethe ansatz equations by using the reflection equations of the open-boundary XXZ model.

In this paper, small diameter InP nanowires with high crystal quality were synthesized through a chemical vapor deposition method. Benefitting from the high crystallinity and large specific surface area of InP nanowires, the simply constructed photodetector demonstrates a high responsivity of up to 1170 AW−1 and an external quantum efficiency of 2.8×105% with a fast rise time of 110 ms and a fall time of 130 ms, even at low bias of 0.1 V. The effect of back-gate voltage on photoresponse of the device was systematically investigated, confirming that the photocurrent dominates over thermionic and tunneling currents in the whole operation. A mechanism based on energy band theory at the junction between metal and semiconductor was proposed to explain the back-gate voltage dependent performance of the photodetectors. These convincing results indicate that fine InP nanowires will have a brilliant future in smart optoelectronics.

Amorphous TbFe films are fabricated by dc magnetron sputtering, and their magnetostrictions at low field are examined over a wide range of terbium content (from 32 at.% to 70 at.%). It is found that the terbium content plays an important role in the magnetic and magnetostrictive properties of TbFe films. TbFe film soft magnetic properties and low field magnetostriction can be efficiently improved by controlling the terbium at an optimum content. The magnetostriction at lower magnetic field is increased with the increase of terbium content up to 48.2 at.%. After reaching the maximum value, further increase of terbium content would result in a great decrease of the low field magnetostriction. By contrast, at higher magnetic field, the magnetostriction is decreased monotonically with the increase of the terbium content.

We theoretically investigate the steady magnetic domain wall driven by spin-orbit torques in the heavy-metal/magnet bilayers with perpendicular anisotropy. Based on collective coordinates method and stability analysis, we analyze the effects of tilted current and Dzyaloshinskii-Moriya interaction on the wall. We find that the wall acquires a sustained motion in the high-current regime by deviating the current from the wall track. Also, a persistent motion can be supported by the competition between spin-orbit torques and Dzyaloshinskii-Moriya interaction in transforming wall type. In the low-current regime, there exist a switching of wall chirality and a reversal of wall motion.

In terms of Darboux transformation, we have exactly solved the higher-order nonlinear Schrodinger equation that describes the propagation of ultrashort optical pulses in optical fibers. We discuss the modulation instability (MI) process in detail and find that the higher-order term has no effect on the MI condition. Under different conditions, we obtain Kuznetsov–Ma soliton and Akhmediev breather solutions of higher-order nonlinear Schrodinger equation. The former describes the propagation of a bright pulse on a continuous wave background in the presence of higher-order effects and the soliton's peak position is shifted owing to the presence of a nonvanishing background, while the latter implies the modulation instability process that can be used in practice to produce a train of ultrashort optical soliton pulses.

The steady motion of magnetic domain wall driven by spin-orbit torques is investigated analytically in the heavy/ferromagnetic metal nanowires for three cases with a current transverse to the in-plane and perpendicular easy axis, and along the in-plane easy axis. By the stability analysis of Walker wall profile, we find that if including the higher-order spin-orbit torques, the Walker breakdown can be avoided in some parameter regions of spin-orbit torques with a current transverse to or along the in-plane easy axis. However, in the case of perpendicular anisotropy, even considering the higher-order spin-orbit torques, the velocity of domain wall cannot be efficiently enhanced by the current. Furthermore, the direction of wall motion is dependent on the configuration and chirality of domain wall with a current along the in-plane easy axis or transverse to the perpendicular one. Especially, the direction of motion can be controlled by the initial chirality of domain wall. So, if only involving the spin-orbit mechanism, it is preferable to adopt the scheme of a current along the in-plane easy axis for enhancing the velocity and controlling the direction of domain wall.

We theoretically investigate the current-induced domain wall resonance in ferromagnetic nanowires with a Dzyaloshinskii-Moriya interaction. The adiabatic and nonadiabatic torques distort the wall's internal structure and exert a global pressure on the wall. An effective Newton's equation is obtained analytically for a domain wall moving in one-dimensional potential and subject to a viscous friction and a driving force. Our results demonstrate that the Dzyaloshinskii-Moriya interaction affects the critical current density for depinning the wall, resonance frequency, and amplitude.

Magnon density distribution can be affected by the spin-transfer torque in a perpendicular ferromagnetic anisotropy nanowire. We obtain the analytical expression for the critical current condition. For the cases of below and above the critical value, the magnon density distribution admits bright and dark soliton states, respectively. Moreover, we discuss two-soliton collision properties that are modulated by the current. Each magnetic soliton exhibits no changes in both velocity and width before and after the collision.

In NiFe/Pt bilayer, when spin current originating from the magnetization procession of NiFe is inject into the adjacent Pt layer under ferromagnetic resonance (FMR), the direct current (DC) voltage VISHE generated by inverse spin Hall effect (ISHE) will be added to the voltage VSRE generated by spin rectification effect (SRE), therefore the measured voltage in experiment is the sum of VISHE and VSRE. It is crucial to separate these contributions, which has been often overlooked before, in order to make a reasonable comparison of the ISHE among different materials. The voltages having symmetric (Lorentz type) and anti-symmetric (dispersive type) components both vary with the static magnetic field strength. However, they have different static magnetic field angle dependences according to our theoretical analysis. In order to distinguish the contribution of ISHE from that of SRE, in this paper, we employ a method, in which the voltage across the sample is measured when the static magnetic field is applied to different directions, to analyze the voltage by varying magnetic field angle in a range from 0° to 360° in steps of 10°, thereby separating the VISHE. The separation is carried out by fitting the angle dependent symmetric and anti-symmetric curves to different theoretical formulas of ISHE and SRE. The voltages of the two different contributions together with the phase angle of the microwave are obtained. At the same time, the FMR line width and the resonant field can be read out. The results show that the ferromagnetic resonance line width in NiFe(20 nm)/Pt(10 nm) sample is larger than that in NiFe(20 nm) sample due to the injection of spin current from NiFe to Pt in the bi-layer sample. We notice that in the curves of voltage vs. static magnetic field, the Lorentz symmetry components of the voltage from the bi-layer sample weight more than those from the single-layer sample. This is explained as a result of the existence of the ISHE in the bi-layer sample, where the spins are pumped from the magnetic layer to the adjacent nonmagnetic layer. The spin pumping effect does not show up in the single-layer sample. There are a large portion of symmetric components in the double layer sample, which is attributed to the ISHE. Although the voltage caused by the SRE is smaller than that by the ISHE, the SRE voltage cannot be ignored. Our work is crucial to understanding the spin-related effects in ferromagnetic/nonmagnetic metal material and provides an improved analysis method to study the spin pumping and the ISHE.

The influence of spin Hall effect on magnetization dynamics is one of the hottest topics in spintronics. In this paper, the magnetization dynamics driven by the spin Hall effect-induced torque in a ferromagnet /heavy metal bilayer structure has been investigated theoretically. By linearizing the Landau-Lifshitz-Gilbert equation which includes the spin Hall effect torque term, and taking stability analysis, the phase diagrams in the plane defined by the current density and external magnetic field have been obtained. Under the control of the current density and external magnetic field, several magnetic states, such as in-plane stable state, in-plane precession and bistable states can be realized. With the external magnetic field oriented within a certain range, the magnetization reversal and precession can be realized through adjusting the current density. In addition, the dynamic evolutions of these magnetic states are demonstrated by solving the temporal evolutive equations numerically.

We review our recent works on dynamics of magnetization in ferromagnet with spin-transfer torque. Driven by constant spin-polarized current, the spin-transfer torque counteracts both the precession driven by the effective field and the Gilbert damping term different from the common understanding. When the spin current exceeds the critical value, the conjunctive action of Gilbert damping and spin-transfer torque leads naturally the novel screw-pitch effect characterized by the temporal oscillation of domain wall velocity and width. Driven by space- and time-dependent spin-polarized current and magnetic field, we expatiate the formation of domain wall velocity in ferromagnetic nanowire. We discuss the properties of dynamic magnetic soliton in uniaxial anisotropic ferromagnetic nanowire driven by spin-transfer torque, and analyze the modulation instability and dark soliton on the spin wave background, which shows the characteristic breather behavior of the soliton as it propagates along the ferromagnetic nanowire. With stronger breather character, we get the novel magnetic rogue wave and clarify its formation mechanism. The generation of magnetic rogue wave mainly arises from the accumulation of energy and magnons toward to its central part. We also observe that the spin-polarized current can control the exchange rate of magnons between the envelope soliton and the background, and the critical current condition is obtained analytically. At last, we have theoretically investigated the current-excited and frequency-adjusted ferromagnetic resonance in magnetic trilayers. A particular case of the perpendicular analyzer reveals that the ferromagnetic resonance curves, including the resonant location and the resonant linewidth, can be adjusted by changing the pinned magnetization direction and the direct current. Under the control of the current and external magnetic field, several magnetic states, such as quasi-parallel and quasi-antiparallel stable states, out-of-plane precession, and bistable states can be realized. The precession frequency can be expressed as a function of the current and external magnetic field.

We investigate theoretically the current-driven domain wall dynamics in heavy-metal-ferromagnet bilayers. Within Lagrangian formalism, the influence of spin Hall effect on the behavior and stability of Walker's profile is analyzed. We find that in the high-current regime, although the spin Hall current alters the wall mobility slightly, the Walker breakdown is removed. In the low-current regime, the spin Hall effect makes the wall motion dependant on the polarity. The static Neel wall can be transformed into Bloch one and the polarity of Bloch wall can be switched. Especially, for proper initial polarity and current, the wall propagates along the current direction.

The transport properties of an artificial single-molecule magnet based on a CdTe quantum dot doped with a single Mn+2 ion (S=5/2) are investigated by the non-equilibrium Green function method. We consider a minimal model where the Mn—hole exchange coupling is strongly anisotropic so that spin-flip is suppressed and the impurity spin S and a hole spin s entering the quantum dot are coupled into spin pair states with (2S+1) sublevels. In the sequential tunneling regime, the differential conductance exhibits (2S+1) possible peaks, corresponding to resonance tunneling via (2S+1) sublevels. At low temperature, Kondo physics dominates transport and (2S+1) Kondo peaks occur in the local density of states and conductance. These peaks originate from the spin-singlet state formed by the holes in the leads and on the dot via higher-order processes and are related to the parallel and antiparallel spin pair states.

A theoretic study is presented on the magnetization dynamics in magnetic multilayers with two tilted spin polarizers. Magnetic phase diagrams are established under the control of the magnitude and direction of dual spin torques. Different magnetic states, including parallel and antiparallel orientations, out-of-plane orientations, in-plane, and out-of-plane precessions, bistable states, can be distinguished in the phase diagrams. For the bistable states, there exists hysteretic switching between static and dynamic states. Selecting different pinned-layer configurations, the reversal between parallel and antiparallel orientation and the switching from stable states to precessional ones can be realized by increasing current. In addition, the dynamic evolutions of magnetic states are demonstrated.

We theoretically investigate the current-excited and adjusted ferromagnetic resonance in magnetic trilayers with a tilted spin polarizer. The current- and frequency-swept resonant spectra are obtained by the linearization method. We find that the precessional frequency, the equilibrium position, the energy pumping and damping, and the resonant linewidth and location can be adjusted by changing the current and the magnetization in the pinned layer. By optimizing the current density and the direction of the pinned magnetization, the energy pumping will be more efficient.