Quasimonochromatic Bright Gamma-ray Generation from Synchronized Compton Scattering via Azimuthal Spatial-Temporal Coupling

High energy photons can be generated via inverse Compton scattering (ICS) in the collision between energetic electrons and intense laser pulse. The development of plasma accelerators promises compact all-optical gamma-ray sources by colliding from wakefield to its high-power driving pulse reflected a mirror. However, law optical focusing hinders realization both high photon yield monochromatic spectrum this scenario. We propose an azimuthal spatial-temporal convertor that decouples focal field strength spot size using helical parabolic geometry. It decomposes beam into train almost identical divergence angle depth, creating synchronized ICS optimized linear regime. scheme resolves dilemma efficiency narrow spread, facilitating generation power lasers beyond relativistic strengths.