It is shown that additional scattering due to tunneling induces a tran
sition of the system from a non-Fermi-liquid into a Fermi-liquid state
as the distance between the Fermi level in the walls and the 2D-band
edge is varied in a double-barrier quantum well, doped with transition
-metal impurities and having an intrinsic two-dimensional continuum. (
C) 1998 American Institute of Physics.