Spins and Momentum in One Dimensional Electron Transport
Experiments on spins and momentum in quasi one-dimensional structures in the GaAs heterostructure will be described. It will be shown that when the momentum degeneracy is lifted by a source-drain voltage a spontaneous spin polarisation occurs. This polarisation is present when the confinement potential is weakened and electrons can relax and form two rows to minimise repulsion.
The spin polarisation can be further investigated by the focussing of electrons in a weak magnetic field. It is shown that inducing the spin polarisation by lifting the momentum degeneracy gives the same results as a large magnetic field which directly lifts the spin degeneracy.