Subject Area A2: Rashba Effect in Two-Dimensional Electron Systems on Metals
Jens Wiebe, Roland Wiesendanger
Up to now the Rashba effect has been studied mainly in semiconductor nanostructures
such as InAs inversion layers.
The Rashba effect leads to the precession of the electron spin if the spin orientation differs from the
orientation of the magnetic field. This spin precession is the basis for the spin transistor proposed by
Supriyo Datta and Biswajit Das. However in semiconductors the Rashba splitting is relatively small.
Compared to semiconductors the Rashba effect in two-dimensional electron systems or metal surfaces
is significantly enhanced.
(a) Scanning-tunneling micrograph of the Au(111) surface with a herring-bone reconstruction.
(b) Chain of seven iron atoms on a Au(111) surface that have been moved together by the tip of a scanning tunneling
In this subject area we want to study the Rashba effect in two-dimensional electronsystems at the interface
of a ferromagnet-metal system with spin-polarized scanning tunneling microscopy.
Magnetic atoms or island will be evaporated on different substrates, for example Au(111),
Bi(110) or Bi/Ag(111).
The spin polarization will be investigated by spin-polarized scanning tunneling spectroscopy.
The magnetization in a ferromagnetic island can be switched by the tip of a scanning tunneling microscope.
When the island is coupled to a chain, this leads to an interesting domino effect.
"Scanning Probe Microscopy and Spectroscopy: Methods and Applications",
Cambridge University Press, Cambridge, U.K. (1994).
S. Krause, L. Berbil Bautista, G. Herzog, M. Bode, and R. Wiesendanger,
"Current-induced magnetization switching with a spin-polarized scanning tunneling
Science 317, 1537-1540 (2007).
F. Meier, L. Zhou, J. Wiebe, and R. Wiesendanger,
"Revealing Magnetic Interactions from Single-Atom Magnetization Curves"
Science 320, 82-86 (2008).
Scattering states of two-dimesional electron systems with Rashba effect
Noncollinear magnetic exchange in atomic nanostructures due to the Rashba effect