Fermi-edge singularity in the vicinity of the resonant scattering condition

V. V. Mkhitaryan, M. E. Raikh

Fermi-edge absorption theory predicting the spectrum, A(ω)\propto ω^{-2δ_0/π+δ^2_0/π^2}, relies on the assumption that scattering phase, δ_0, is frequency-independent. Dependence o…