Ground-state properties of **spin**-orbit-coupled dipolar Bose-Einstein
condensates with in-plane gradient magnetic field

**orbit**coupling (SOC), dipole-dipole interaction (DDI) and the in-plane quadrupole field on the ground-state structures and

**spin**textures of the system are systematically analyzed and discussed. Expand abstract.

**spin**-orbit-coupled pseudo-spin-1/2 dipolar Bose-Einstein condensates (BECs) in a two-dimensional harmonic trap and an in-plane quadrupole field. The effects of

**spin**-

**orbit**coupling (SOC), dipole-dipole interaction (DDI) and the in-plane quadrupole field on the ground-state structures and

**spin**textures of the system are systematically analyzed and discussed. For fixed SOC and DDI strengths, the system shows a quadrupole stripe phase with a half-quantum vortex, or a quadrupole Thomas-Fermi phase with a half-quantum antivortex for small quadrupole field strength, depending on the ratio between inter- and intraspecies interaction. As the quadrupole field strength enhances, the system realizes a ring mixed phase with a hidden vortex-antivortex cluster rather than an ordinary giant vortex in each component. Of particular interest, when the strengths of DDI and quadrupole field are fixed, strong SOC leads to the formation of criss-crossed vortex string structure. For given SOC and quadrupole field, the system for strong DDI displays a sandwich-like structure, or a special delaminated structure with a prolate antivortex in the

**spin**-up component. In addition, typical

**spin**textures for the ground states of the system are analyzed. It is shown that the system sustains exotic topological structures, such as a hyperbolic

**spin**domain wall, skyrmion-half-antiskyrmion-antiskyrmion lattice, half-skyrmion-skyrmion-half-antiskyrmion lattice, and a drum-shaped antimeron.

10/10 relevant

arXiv

Topological excitations in rotating Bose-Einstein condensates with
Rashba-Dresselhaus **spin**-**orbit** coupling in a two-dimensional optical lattice

**spin**textures of rotating two-component Bose-Einstein condensates (BECs) with Rashba-Dresselhaus spin-

**orbit**coupling (RD-SOC), which are confined in a two-dimensional (2D) optical lattice plus a 2D harmonic trap. Expand abstract.

**spin**textures of rotating two-component Bose-Einstein condensates (BECs) with Rashba-Dresselhaus

**spin**-

**orbit**coupling (RD-SOC), which are confined in a two-dimensional (2D) optical lattice plus a 2D harmonic trap. In the absence of rotation, a relatively small isotropic 2D RD-SOC leads to the generation of ghost vortices for initially miscible BECs, while it gives rise to the creation of rectangular vortex-antivortex lattices for initially immiscible BECs. As the strength of the 2D RD-SOC enhances, the visible vortices or the 2D vortex-antivortex chains are created for the former case, whereas the rectangular vortex-antivortex lattices are transformed into vortex-antivortex rings for the later case. For the initially immiscible BECs with fixed 2D RD-SOC strength, the increase of rotation frequency can result in the structural phase transition from square vortex lattice to irregular triangular vortex lattice and the system transition from initial phase separation to phase mixing. In addition, we analyze the combined effects of 1D RD-SOC and rotation on the vortex configurations of the ground states for the case of initial phase separation. The increase of 1D SOC strength, rotation frequency or both of them may result in the formation of vortex chain and phase mixing. Furthermore, the typical

**spin**textures for both the cases of 2D RD-SOC and 1D RD-SOC are discussed. It is shown that the system favors novel

**spin**textures and skyrmion configurations including an exotic skyrmion-half-skyrmion lattice (skyrmion-meron lattice), a complicated meron lattice, a skyrmion chain, and a Bloch domain wall.

10/10 relevant

arXiv

Giant anisotropy of Gilbert damping in a Rashba honeycomb antiferromagnet

**spin**-

**orbit**coupling in a two-dimensional antiferromagnet on a honeycomb lattice. The phenomenon originates in

**spin**-

**orbit**induced splitting of conduction electron subbands that strongly suppresses certain

**spin**-flip processes. As a result, the

**spin**-

**orbit**interaction is shown to support an undamped non-equilibrium dynamical mode that corresponds to an ultrafast in-plane N\'eel vector precession and a constant perpendicular-to-the-plane magnetization. The phenomenon is illustrated on the basis of a two dimensional $s$-$d$ like model.

**Spin**-

**orbit**torques and conductivity are also computed microscopically for this model. Unlike Gilbert damping these quantities are shown to reveal only a weak anisotropy that is limited to the semiconductor regime corresponding to the Fermi energy staying in a close vicinity of antiferromagnetic gap.

7/10 relevant

arXiv

Internal magnetic fields, **spin**-**orbit** coupling, and **orbital** period
modulation in close binary systems

**orbital**period observed in close stellar binary systems based on an angular momentum exchange between the

**spin**of the active component and the

**orbit**al motion. Expand abstract.

**orbital**period observed in close stellar binary systems based on an angular momentum exchange between the

**spin**of the active component and the

**orbital**motion. This

**spin**-

**orbit**coupling is not due to tides, but is produced by a non-axisymmetric component of the gravitational quadrupole moment of the active star due to a persistent non-axisymmetric internal magnetic field. The proposed mechanism easily satisfies all the energy constraints having an energy budget about 100-1000 times smaller than those of previously proposed models and is supported by the observations of persistent active longitudes in the active components of close binary systems. We present preliminary applications to three well-studied binary systems to illustrate the model. The case of stars with hot Jupiters is also discussed showing that no significant

**orbital**period modulation is generally expected on the basis of the proposed model.

10/10 relevant

arXiv

Efficient **spin**-**orbit** torque switching with non-epitaxial chalcogenide
heterostructures

**spin**-

**orbit**torques (SOTs) generated from topological insulators (TIs) have gained increasing attention in recent years. These TIs, which are typically formed by epitaxially grown chalcogenides, possess extremely high SOT efficiencies and have great potential to be employed in the next-generation spintronics devices. However, epitaxy of these chalcogenides is required to ensure the existence of topologically-protected surface state (TSS), which limits the feasibility of using these materials in industry. In this work, we show that non-epitaxial Bi$_{x}$Te$_{1-x}$/ferromagnet heterostructures prepared by conventional magnetron sputtering possess giant SOT efficiencies even without TSS. Through harmonic voltage measurement and hysteresis loop shift measurement, we find that the damping-like SOT efficiencies originated from the bulk

**spin**-

**orbit**interactions of such non-epitaxial heterostructures can reach values greater than 100% at room temperature. We further demonstrate current-induced SOT switching in these Bi$_{x}$Te$_{1-x}$-based heterostructures with thermally stable ferromagnetic layers, which indicates that such non-epitaxial chalcogenide materials can be potential efficient SOT sources in future SOT magnetic memory devices.

10/10 relevant

arXiv

Resolving Ultra-Fast **Spin**-**Orbit** Dynamics in Heavy Many-Electron Atoms

**spin**-

**orbit**effects included, to study krypton irradiated by two time-delayed XUV ultrashort pulses. The first pulse excites the atom to 4s$^{2}$4p$^{5}$5s. The second pulse then excites 4s4p$^{6}$5s autoionising levels, whose population can be observed through their subsequent decay. By varying the time delay between the two pulses, we are able to control the excitation pathway to the autoionising states. The use of cross-polarised light pulses allows us to isolate the two-photon pathway, with one photon taken from each pulse.

10/10 relevant

arXiv

Ferromagnetic fluctuations in the Rashba-Hubbard model

**spin**susceptibility of the $t$-$t'$-Rashba-Hubbard model on the square lattice. The combined effect of the second-neighbor hopping $t'$ and the

**spin**-

**orbit**coupling leads to ferromagnetic fluctuations in a broad filling region. The

**spin**-

**orbit**coupling splits the energy bands, leading to two van Hove fillings, where the sheets of the Fermi surface change their topology. Between these two van Hove fillings the model shows ferromagnetic fluctuations. We find that these ferromagnetic fluctuations originate from interband contributions to the

**spin**susceptibility. These interband contributions only arise if there is one holelike and one electronlike Fermi surface, which is the case for fillings in between the two van Hove fillings. We discuss implications for experimental systems and propose a test on how to identify these types of ferromagnetic fluctuations in experiments.

5/10 relevant

arXiv

Excitonic Magnetism at the intersection of **Spin**-**orbit** coupling and
crystal-field splitting

**spin**-

**orbit**coupled $t_{2g}$ orbitals. However, uncontested material examples for its realization are rare. Applying the Variational Cluster Approach to the square lattice, we find conventional

**spin**antiferromagnetism combined with

**orbital**order at weak and excitonic order at strong

**spin**-

**orbit**coupling. We address the specific example of Ca$_2$RuO$_4$ using ab-initio modeling and conclude it to realize excitonic magnetism despite its pronounced

**orbital**polarization.

10/10 relevant

arXiv

Global phase diagram of a **spin**-**orbital** Kondo impurity model and the
suppression of Fermi-liquid scale

**spin**-

**orbital**Kondo model, using the numerical renormalization group (NRG) method and compute its global phase diagram. In this framework, $T_{\text{FL}}$ becomes arbitrarily small close to two new quantum critical points (QCPs) which we identify by tuning the

**spin**or

**spin**-

**orbital**Kondo couplings into the ferromagnetic regimes. We find quantum phase transitions to a singular Fermi-liquid or a novel non-Fermi-liquid phase. The new non-Fermi-liquid phase shows frustrated behavior involving alternating overscreenings in

**spin**and

**orbital**sectors, with universal power laws in the

**spin**($\omega^{-1/5}$),

**orbital**($\omega^{1/5}$) and

**spin**-

**orbital**($\omega^1$) dynamical susceptibilities. These power laws, and the NRG eigenlevel spectra, can be fully understood using conformal field theory arguments, which also clarify the nature of the non-Fermi-liquid phase.

9/10 relevant

arXiv

Squeezing Magnetic Modulations by Enhanced **Spin**-**Orbit** Coupling of 4d
Electrons in the Polar Semiconductor GaMo$_4$S$_8$

**spin**-

**orbit**coupling (SOC) than the known skyrmion-hosts mainly composed of $3d$ transition metals. The enhanced SOC produces a variety of modulated phases with very short periodicity, $\lambda

10/10 relevant

arXiv