Double-atomic layer of Tl on Si(111): Atomic arrangement and electronic properties
Journal
Surface Science
Journal Volume
668
Start Page
17
End Page
22
ISSN
00396028
Date Issued
2018
Author(s)
Mihalyuk, Alexey N.
Bondarenko, Leonid V.
Tupchaya, Alexandra Y.
Gruznev, Dimitry V.
Hsing, Cheng-Rong
Wei, Ching-Ming
Zotov, Andrey V.
Saranin, Alexander A.
Abstract
Metastable double-atomic layer of Tl on Si(111) has recently been found to display interesting electric properties, namely superconductivity below 0.96 K and magnetic-field-induced transition into an insulating phase intermediated by a quantum metal state. In the present work, using a set of experimental techniques, including low-energy electron diffraction, scanning tunneling microscopy, angle-resolved photoelectron spectroscopy, in a combination with density-functional-theory calculations, we have characterized atomic and electronic properties of the Tl double layer on Si(111). The double Tl layer has been concluded to contain ∼ 2.4 monolayer of Tl. A top Tl layer has a ‘1 × 1’ basic structure and displays 6 × 6 moiré pattern which originates from various residence sites of Tl atoms. Upon cooling below ∼ 140 K, the 6 × 6 moiré pattern changes to that having a 63×63 periodicity. However, the experimentally determined electron band dispersions show a 1 × 1 periodicity. The calculated band structure unfolded into the 1 × 1 surface Brillouin zone reproduces well the main features of the photoelectron spectra. © 2017 Elsevier B.V.
Subjects
Angle-resolved photoelectron spectroscopy
Atom–solid interactions
First-principal calculations
Scanning tunneling microscopy
Silicon
Thallium
SDGs
Publisher
Elsevier B.V.
Type
journal article