Negative and positive dust grain effect on the modulation instability of an intense laser propagating in a hot magnetoplasma

The modulation instability of intense circularlypolarized laser beam in hot magnetized dusty plasma isstudied. A nonlinear equation describing the interaction oflaser with dusty plasma in the quasi-neutral approximationis derived. The effect of negative and positive dust grainson the laser modulation growth rate is studied. It is shownthat the existence of positive dust grains instead of ions cansubstantially improve the modulation growth rate.