Nonreciprocal light diffraction by a vortex magnetic particle of spherical shape

Abstract

We report a theoretical study of light diffraction by a spherical magnetic particle with a vortex magnetization distribution. It is shown that the intensity of the diffracted light involves a nonreciprocal contribution. This contribution depends on the vorticity of particle magnetization. It appears due to the excitation of an electric quadrupole, magnetic dipole and the addition to the electric dipole moment in the particle, that depend on the particle magnetization vorticity. The estimation of the non-reciprocal contrbution for a cobalt particle and two linear polarizations of the incident light fits the data of recent experimental studies in the lattice of triangle magnetic particles by an order of magnitude.

Фотогальванический Эффект В Ферромагнетике Со Спин-Орбитальным Взаимодействием

“…Параметры расчета приведены на рисунке. 2 , где g(α R ) -функция модуля вектора Рашбы. Такой ток вызван волной и протекает в неравновесной системе, а потому не запрещен.…”

“…Связь спиновых и орбитальных степеней свободы в ферромагнетиках приводит к ряду необычных и интересных явлений в оптике и транспорте. В неколлинеарных ферромагнетиках возникают такие явления, как невзаимное рассеяние света [1,2] и генерация сигнала на удвоенной частоте [3], поглощение и излучение электромагнитных волн за счет переходов электронов проводимости между спиновыми подзонами [4][5][6][7][8]. В некомпланарных магнитных системах наблюдается топологический эффект Холла [9][10][11], эффект выпрямления для нейтронов [12][13][14] и электронов [15][16][17].…”

Photovoltaic effect in a ferromagnet with spin-orbit coupling

“…-, Fermi momentum for two spin subbands (ε F -Fermi energy). Photocurrent (16) can be described by the phenomenological expression g(α R )[α R × M](EM) 2 , where g(α R )function of the Rasba vector module. Such current is caused by a wave and flows in an nonequilibrium system, and therefore is not prohibited.…”

Nonreciprocal Mechanical Squeezing in a Spinning Optomechanical System

“…It has been achieved in systems based on the magneto‐optical Faraday rotation effect, [ 1–4 ] the modulation of the refractive index, [ 5–7 ] parity‐time‐symmetric structures, [ 8–10 ] and so on. The concept of nonreciprocity is even extended to the other aspects of a light, such as nonreciprocal diffraction, [ 11–13 ] directional lasing, [ 14–16 ] and directional nonclassical effects of light. [ 17–20 ] On the other hand, cavity optomechanical (COM) systems are important platforms for controlling the mechanical response of a system by an optical field and, reversely, its optical response by a mechanical motion.…”