  We report on the optical realization of the magneto-intersubband oscillations
that have been measured in the sub-terahertz transmittance of a GaAs quantum
well with two subbands occupied. Following their dc analogue, the oscillations
are periodic in the inverse magnetic field with the period governed by the
subband gap. Their magnitude and polarization dependence accurately follow the
presented simplified version of the dynamic magneto-intersubband oscillations
equation that naturally combines dc magneto-intersabband oscillations with
microwave-induced resistance oscillations (MIRO). Simultaneously measured
photoresistance also reveals its strong sensitivity to the sign of the circular
polarization, proving the used theoretical modeling.
