Spin-other-orbit effect of photon modes

With exact wavefunctions for a non-relativistic electron interacting with a two-mode intense photon field propagating in two perpendicular directions, obtained by solving a Schrodinger-like equation, we predict a previously u nknown 'spin-other-orbit' effect of photon modes. A multiphoton ionization experiment to test this effect is suggested. Transition rates which manifes t 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.