Orbital selective overlayer-substrate hybridization in a Pb monolayer on Ag(111)

Abstract

The electronic structure of a Pb overlayer on Ag͑111͒ has been studied by angle-resolved photoemission spectroscopy. We identify three p bands. While the p xy bands are sharp and closely resemble the corresponding bands of a free-standing Pb layer, the p z band is strongly spread in energy and momentum. Tight-binding calculations of the electronic structure combined with structural calculations using the embedded atom method indicate a symmetry dependent hybridization with the Ag͑111͒ surface. We propose a symmetry selective, surface state mediated coupling to the bulk continuum which results in a broadened line shape for the p z band only.

Combined ARPES and STM study of Pb/Au(111) Moiré structure: One overlayer, two symmetries

“…The behavior of the two Pb p xy states is remarkably different: one adjusts to the symmetry of the Au(111) substrate, whereas the other displays the symmetry of the two-domain modulated overlayer. The p z state is strongly broadened in energy and momentum, similar to previous observations for Pb MLs on Ag(111) 7 and on Cu(111). 18 These differences reflect the orbital-dependent hybridization of the three interface states with the continuum of substrate bulk states.…”

“…2(b). Previous tight-binding calculations performed for dense Pb monolayers on Cu(111) and Ag(111), 7,18,20 found three Pb-derived bands: a band with p z orbital character with the smallest Fermi wave vector, hereafter labeled Pb1, and two bands with p xy character, labeled Pb2 and Pb3. The same picture is also consistent with our data, namely with the multisheet Fermi surface of Fig.…”

“…[1][2][3] Characteristic signatures of superperiodicities have been observed by ARPES in bulk materials [4][5][6] and at ordered interfaces. [7][8][9][10][11][12][13][14][15][16] Lead overlayers on both metallic and semiconducting substrates are especially interesting in this respect. It is found that, due to their high lateral stiffness, monolayers (ML) of Pb form dense Moiré superstructures.…”

Aperiodic and modulated Pb thin films on fivefold icosahedral Al-Cu-Fe and Al(111): Tailoring the structure of Pb

“…Moiré patterns are frequently observed for incommensurate systems, not only in metal-on-metal systems but for other systems as well. [36][37][38] A general property of such superstructures is that the lateral interaction within the film must be large compared to substrate-film lateral interaction in order to be formed. Experimentally, a hexagonal moiré pattern has been observed by STM ͑Ref.…”

Manipulating quantum-well states by surface alloying: Pb on ultrathin Ag films

“…In fact, these states have been observed in Pb/Ag alloys at single crystal Ag surfaces and have been reported to be largely spin-split. 34,35 They cross the Fermi level at 3-4 degrees off-normal and the Fermi wave number k F is 0.14 Å −1 , as shown by the white arrowhead. The parabolic dispersion of the QWSs seem to be disturbed where they intersect with the surface states possibly due to hybridization effects.…”