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In the current stage, valley-contrasting physics is mainly rooted in nonmagnetic and/or ferromagnetic hexagonal lattices and is rarely used to observe the simultaneous spin and valley polarization in antiferromagnetic materials. In this work, we propose a general scheme that can be achieved easily in experiments to break the P T joint symmetry of antiferromagnetic structures, that is, introducing an out-of-plane potential gradient to realize spin–valley splitting and spontaneous valley polarization. In combination of the model analysis and first-principles calculations, we translate the concept into Mn2P2X3Y3 monolayers and clarify the valley-related physics. It is obvious that our finding significantly extends the scope of valleytronics in both theory and experiments. [ABSTRACT FROM AUTHOR]

Since the first evidence of a global polarization of Λ hyperons in relativistic nuclear collisions in 2017, spin has opened a new window in the field, both at experimental and theoretical level, and an exciting perspective. The current state of the field is reviewed with regard to the theoretical understanding of the data, reporting on the most recent achievements and envisioning possible developments. The intriguing connections of spin physics in relativistic matter with fundamental questions in quantum field theory and applications in the non-relativistic domain are discussed. [ABSTRACT FROM AUTHOR]

A mesoscopic multi-terminal superconducting Nb strip with a spin injection terminal has been developed. We investigate the influence of spin polarization on the relaxation process of the quasiparticle in the superconducting Nb. The position dependence of the nonlocal voltage provides the quasiparticle relaxation length. The relaxation length for the spin-polarized quasiparticle is found to show a 12.5% increase from that for the un-polarized quasiparticle. This demonstration opens a new avenue for utilization of the spin current in a superconducting device. [ABSTRACT FROM AUTHOR]

We study a single dark N2 electron spin defect in diamond, which is magnetically coupled to a nearby nitrogen-vacancy (NV) center. We perform pulsed electron spin resonance on this single spin by mapping its state to the NV center spin and optically reading out the latter. Moreover, we show that the NV center's spin polarization can be transferred to the electron spin by combined two decoupling control-NOT gates. These two results allow us to extend the NV center's two key properties-optical spin polarization and detection—to any electron spin in its vicinity. This enables dark electron spins to be used as local quantum registers and engineerable memories. [ABSTRACT FROM AUTHOR]

A new method to produce spin-polarized radioactive nuclear beams has been developed, which takes advantage of the low-energy transfer reaction in inverse kinematics. The method provides beam energies of a convenient range so that they may be implanted in a thin stopper, yet allowing the stopper to be spatially separated from the production target. The presence of polarizations of sizes at least $\left|P\right|\sim 0.5 \%$ has been confirmed for a 17N beam obtained from 9Be(18O,17N) reaction at $\theta_{\rm Lab} \sim -1.7\,^{\circ}$ . [ABSTRACT FROM AUTHOR]

The effects of electro-magnetic confining potentials and the s–d exchange interaction between substituted Mn ions and carriers on the spin polarization of carriers in an diluted magnetic semiconductor quantum dot are investigated within the framework of the effective-mass theory. The energy eigenvalues and wavefunctions of a single electron in the presence of an external magnetic field are studied by solving the one particle Schrödinger equation including the conventional Zeeman effect, the s–d exchange interaction and the electric confining potential which describes the dot. The eigenenergy structure for low lying states is strongly dependant on the relative sizes of the s–d exchange interactions and the conventional Zeeman energy splitting. When the spin splitting exceeds the cyclotron energy splitting, the Landau level overlappings occur so that the spin polarization of carriers is induced in low lying energy states. This spin polarization of carriers in the diluted magnetic semiconductor quantum dot can be controlled by changing the electro-magnetic confining potentials. [ABSTRACT FROM AUTHOR]

The current induced local spin polarization due to weak Rashba spin-orbit coupling in narrow strip is studied. In the presence of longitudinal charge current, local spin polarizations appear in the sample. The spin polarization perpendicular to the plane has opposite sign near the two edges. The in-plane spin polarization in the direction perpendicular to the sample edges also appears, but does not change sign across the sample. From our scaling analysis based on increasing the strip width, the out-of-plane spin polarization is important mainly in a system of mesoscopic size, and thus appears not to be associated with the spin-Hall effect in bulk samples. [ABSTRACT FROM AUTHOR]

We theoretically investigate the spin-dependent transport properties of electrons in realistic magnetic-electric barrier nanostructures, which are produced by the deposition, on top of a heterostructure, of a metallic ferromagnetic stripe with an applied voltage. The degree of the electron-spin polarization is found to be closely associated with this voltage, although the use of applied voltage itself induces no spin polarization effect. As a positive voltage is applied to the stripe the electron-spin polarization shifts towards the low-energy region and increases; it shifts towards the high-energy direction and reduces for a negative applied voltage. These results shown in this work imply that the degree of electron-spin polarization can be tuned by means of an applied voltage on the stripes of system, which may result in a practical voltage-controlled spin filter. [ABSTRACT FROM AUTHOR]

We study the magnetization and the magnetic phases of II-VI-based n-doped nonmagnetic- semiconductor (NMS) / narrow to wide dilute-magnetic-semiconductor (DMS) / n-doped NMS quantum wells under in-plane magnetic field. The parallel magnetic field is used as a tool, in order to achieve non-step-like density of states in these -appropriate for conduction-band spintronics- structures. [ABSTRACT FROM AUTHOR]

We propose a new method, using the Andreev reflection at superconductors, to measure parity violation induced by the standard electroweak theory, which in turn constrains the possible parity-violating effects of new physics. The weak neutral currents induce parity-violating, marginal effective operators, though quite tiny, in superconductors. We estimate their effects on superconducting gaps and propose a method to measure the parity-violation from the spin polarization effect, when electrons or holes get Andreev-reflected at the interface between normal metal and a superconductor. Such polarization effects might be comparable to the atomic parity violation and thus naturally give an interesting bound on certain models of new physics, that couples to electrons, such as Majorana mass of active neutrinos or doubly charged Higgs. [ABSTRACT FROM AUTHOR]