  We develop a theory of the coherent photogalvanic effect (CPGE) in
low-dimensional superconductors in the fluctuating regime. It manifests itself
in the appearance of a stationary electric current of Cooper pairs under the
action of two coherent electromagnetic fields of light with frequencies lying
in the sub-terahertz range. We derive the general formula for the electric
current density, study the particular cases of linear and circular
polarizations of the external light fields, and show that the current might
have a non-monotonous spectrum at certain polarization angles and turns out
very sensitive to the proximity of the ambient temperature to the critical
temperature of superconducting transition: Approaching the critical
temperature, the peak in the spectrum becomes narrower, its frequency
experiences a redshift, and the intensity of the peak drastically grows.
