This study experimentally investigated the effects of repetitive laser energy deposition using a supersonic intake model with a central conical compression surface and a cross-sectional duct in a Mach 1.92 indraft wind tunnel: especially in the subcritical and buzz modes. A single-pulse energy deposition was observed to suppress the flow separation at the compression surface by “sweeping” a shock wave system with the thermal bubble generated by the energy deposition. The duration of the sweeping effect was approximately in the subcritical mode and in the buzz mode. Furthermore, repetitive deposition of laser pulse energies was observed to moderate instabilities in both modes, and it increased the pressure recovery by as much as 8%; also, the occurrence of buzz was delayed, thereby widening the stable, subcritical regime. In both modes, there was a threshold value for the laser pulse repetition frequency , which corresponded to the duration of the sweeping effect (e.g., in subcritical mode). Below this frequency, the increase in the pressure was proportional to the repetition frequency; whereas above , the effect per single pulse was reduced.