Electronic and transport properties of Pb-dense reconstructions on Si(100)

Abstract

Electronic and transport properties of the dense Pb/Si(100) reconstructions, 2×1-Pb with 1.5 ML (monolayer) of Pb and c(4×4)-Pb with ∼1.875 (15/8) ML of Pb, have been explored using angle-resolved photoelectron spectroscopy in conjunction with the DFT calculations and in situtransport and magnetotransport four-probe measurements at low temperatures. Both reconstructions are the low-dimensional materials with the advanced properties. In particular, the Pb/Si(100)2×1 shows up as a quasi-one-dimensional metallic phase with an extremely great spin splitting of the metallic surface-state band as revealed by the DFT calculations. The Pb/Si(100)c(4×4) has been found to demonstrate fingerprints of a superconductor with a critical temperature of 1.03 K. At low temperatures, the reconstructions display quantum phenomena relevant to their low-dimensional nature, e.g., metal-insulator transition for the Pb/Si(100)2×1 and magnetic-field-induced superconductor-insulator transition for the Pb/Si(100)c(4×4).