  An all-optical scheme is proposed for studying a laser-plasma based
incoherent photon emission from inverse Compton scattering in quantum
electrodynamic (QED) regime. A theoretical model is presented to explain the
coupling effect among radiation reaction trapping, self-generated magnetic
field and spiral attractor in phase space, which guarantees the energy and
angular momentum (AM) transformation from electromagnetic fields to particles.
Taking advantage of a prospective $\sim$10$^{23}$W/cm$^{2}$ laser facility, 3D
Particle-in-cell (PIC) simulations manifest the present gamma-ray flash with an
unprecedented power of multi-petawatt (PW) and brightness of
1.7$\times$10$^{23}$photons/s/mm$^2$/mrad$^2$/0.1$\%$bandwidth (at 1GeV). These
results bode well for new research direction in particle physics and laboratory
astrophysics while exploring laser plasma interaction.
