Semiconductor to metal transition in strictly two dimension-a comparative study on GaAs and carbon nanotube

Choosing GaAs, donor binding energies in two dimension are obtained using Thomas-Fermi and Hartree screening functions within the effective mass approximation. Binding energies are computed both in the hydrogen atom model and D- ion model. The results show the non-feasibility of semiconductor-to-metal transition (SMT) in two-dimensional system of GaAs. For curiosity we have obtained the donor binding energies in carbon nanotube (CNT), a highly correlated system by considering it as two-dimensional structure. We could observe the feasibility of SMT in CNT. This indicates the strong confinement in nanostructures and the results will be useful for nanodevice fabrication.