X-ray response of the Luttinger model.

Abstract

We study the x-ray response of an exactly solvable model of a Luttinger liquid coupled to a core level in one dimension. The power-law singularities in photoemission and x-ray absorption for a free Fermi gas are found to survive with modified exponents for a Luttinger system of finite compressibility. We also show that the singularities disappear in compressible systems even in the absence of a plasmon gap in the conduction band.