  Modulation of the charge carrier density in a Mott material by remote doping
from a highly doped conventional band insulator is proposed to test theoretical
predictions of band filling control of the Mott metal-insulator transition
without introducing lattice distortions or disorder, as is the case for
chemical doping. The approach is experimentally tested using ultrathin (2.5 nm)
NdNiO3 films that are epitaxially grown on La-doped SrTiO3 films. We show that
remote doping systematically changes the charge carrier density in the NdNiO3
film and causes a moderate shift in the metal-insulator transition temperature.
These results are discussed in the context of theoretical models of this class
of materials exhibiting a metal-insulator transition.
