Chirality as generalized spin–orbit interaction in spintronics

Chirality or handedness distinguishes an object from its mirror images, such as the spread thumb, index finger, and middle finger of right left hand. In mathematics, it is described by outer product three vectors that obey a right-hand vs. left-hand rule. The chirality ground state magnetic textures defined magnetization, gradient, electric field broken inversion symmetry can be fixed strong relativistic spin–orbit interaction. This review focuses on observed in excited states order, dielectrics, conductors hold transverse spins when they are evanescent. Even without any effect, spin evanescent waves locked to momentum surface normal their propagation plane. thereby acts generalized interaction, which leads discovery various chiral interactions between magnetic, phononic, electronic, photonic, plasmonic excitations spintronics mediate excitation quasiparticles into single direction, leading phenomena phonon pumping, Seebeck, skin, magnonic trap, magnon Doppler, damping, diode effects. Intriguing analogies with counterparts nano-optics plasmonics exist. After brief concepts characterize chirally coupled magnets spintronics, we turn states. We present unified electrodynamic picture for dynamical terms interaction compare plasmonics. Based general theory, subsequently theoretical progress experimental evidence well near-field transfer spins, electronic phononic nanostructures at GHz time scales. provide perspective future research before concluding this article.