Spin-Other-Orbit Effect in Two-Mode Multiphoton Ionization

A previously unknown “spin-other-orbit”effect of photon modes is predicted by solving a Schrödinger-like equation for a nonrelativistic electron interacting with a two-mode intense photon field propagating in two perpendicular directions. A multiphoton ionization experiment to test this effect is suggested. Transition rates which manifest this effect to be measured in the experiment are calculated and presented graphically. A detailed comparison between this effect and the well-known spin-other-orbit effect of electrons is included.