  In this paper we attempt to reconstruct one of the last projects of Volodya
Geyler which remained unfinished. We study motion of a quantum particle in the
plane to which a halfline lead is attached assuming that the particle has spin
$\frac12$ and the plane component of the Hamiltonian contains a spin-orbit
interaction of either Rashba or Dresselhaus type. We construct the class of
admissible Hamiltonians and derive an explicit expression for the Green
function applying it to the scattering in such a system.
