Electronic properties of silicene and the role of the electron-pair states in unconventional superconductivity

• Grant number: 13/03023-1
• Support Opportunities: Scholarships abroad - Research
• Start date: August 01, 2013
• End date: July 31, 2014
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Hai Guoqiang
• Grantee: Hai Guoqiang
• Host Investigator: Francois M. Peeters
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Institution abroad: University of Antwerp (UA), Belgium

Abstract

This research project is composed of two parts. (1) The first part is aimed to study the electronic properties of silicene. Silicene is a new material similar to graphene but with a gap at the Dirac point, a linear spectrum near the K and K' points, and very strong spin-orbit interaction. It has been created very recently in laboratories. In this project, we are going to study (i) the magneto-transport properties in silicene, especially for frequency-dependent transport and power spectrum calculations; and (ii) the electron-electron interaction in a silicene layer. (2) In the second part, we will study the electron-pair states for unconventional superconductivity. Recently, we find a metastable electron-pair energy band in a two-dimensional crystal. The wavefunction of the pair is given by a Bloch wave in the center-of-mass coordinate and the two strongly correlated electrons are bound in the same unit cell in the relative coordinate. We also show that the presence of holes in a many-electron system is essential to stabilize the electron pair. In this part of the project, we are going to calculate the self-energies of the electron-pairs and holes in a 2D many-body Boson-Fermion system. We will extend our calculations to three-dimensional system and also study the properties of the electron-pair states in magnetic fields and the Meissner effect. (AU)