Kinetic Phenomena in a Semiconductor Excited by an Oriented Beam of Fast Particles

It is shown that the passage of channeled particles through a crystal without a center of symmetry or in a magnetic field leads to the appearance of a current, i.e., quasi-photogalvanic and quasi-photomagnetic effects. The theory of these phenomena is developed. The orientation dependence of the quasi-photomagnetic and quasi-photogalvanic currents on the entry angle of a channeled particle with respect to the crystallographic planes is predicted. The dependence of the effect on the state and quantum transitions of a channeled particle is studied. The contribution of matrix elements of the first and second kinds to the quasi-photogalvanic effect is investigated. The intensity of the quasi-photogalvanic current induced by the nondipole radiation of hard photons generated by a high-energy channeled particle is estimated.