E. Ribeiro et al., Metal-insulator transition in a disordered two-dimensional electron gas inGaAs-AlGaAs at zero magnetic field, PHYS REV L, 82(5), 1999, pp. 996-999
A metal-insulator transition in two-dimensional electron gases at B = 0 is
found in Ga[Al]As heterostructures, where a high density of self-assembled
InAs quantum dots is incorporated just 3 nm below the heterointerface. The
transition occurs at resistances around h/e(2) and critical carrier densiti
es of 1.2 X 10(11) cm(-2). Effects of electron-electron interactions are ex
pected to be rather weak in our samples, while disorder plays a crucial rol
e.