  The effect of photon-beam-induced turbulence on propagation of radio emission
in a pulsar magnetosphere is discussed. Beamed radio emission with a high
brightness temperature can generate low-frequency plasma waves in the pulsar
magnetosphere and these waves scatter the radio beam. We consider this effect
on propagation of radio emission both in the open field line region and in the
closed field line region. The former is applicable to most cases of pulsar
radio emission where the propagation is confined to the polar region; it is
shown that the induced process is not effective for radio emission of
moderately high brightness temperature but can have a severe effect on giant
pulses. For giant pulses not to be affected by this process, they must be
emitted very close to the light cylinder. We show that the induced process is
efficient in the closed field line region, inhibiting propagation of the radio
emission in this region.
