  Electron backscattering is introduced as mechanism to enhance high-harmonic
generation in solid-state like systems with broken translational symmetry. As a
paradigmatic example we derive for a finite chain of $N$ atoms the harmonic
cut-off through backscattering of electrons in the conduction band from the
edges of the chain. We also demonstrate a maximum in the yield of the high
harmonics from the conduction band if twice the quiver amplitude of the driven
electrons equals the length of the chain. High-harmonic spectra as a function
of photon energy are shown to be equivalent if the ratio of chain length to the
wavelength of the light is kept constant. Our quantum results are corroborated
by a (semi-)classical trajectory model with refined spatial properties required
to describe dynamics with trajectories in the presence of broken translational
symmetry.
