We propose a new method for dynamic nuclear polarisation in a quasi one-dimensional quantum wire utilising the spin-orbit interaction, the hyperfine interaction, and a finite sourcedrain potential difference. In contrast with current methods, our scheme does not rely on external magnetic or optical sources which makes independent control of closely placed devices much more feasible. Using this ...

The significance of nuclear spin polarisation in time-resolved optical studies of III-V semiconductors is addressed. Electron Larmor beats in pump-probe reflectivity from a GaAs/AlGaAs quantum well show Overhauser shift of 0.7 T due to accumulated nuclear polarisation 〈I〉/I=0.065. This leads to precision values of electron g-factor, elucidates nuclear spin pumping and diffusion mechanisms in qu...

This thesis studies electron spin phenomena in lateral semi-conductor quantum dots/anti-dots and electron conductance in graphene nanoribbons by numerical modelling. In paper I we have investigated spin-dependent transport through open quantum dots, i.e., dots strongly coupled to their leads, within the Hubbard model. Results in this model were found consistent with experimental data and sugges...

Photoelectron spin-polarisation measurements of In(5s2 5p) 2P,12 were performed in the autoionisation region of the 5s5p2-configuration using monochromatic circularly polarised synchrotron radiation at the electron storage ring BESSY. The autoionising levels are analysed in terms of partial cross section, dipole matrix elements and phase-shift differences. In addition the measured photoelectron...

The sensitivity of Magnetic Resonance Imaging (MRI) depends strongly on nuclear spin polarisation and, motivated by this observation, dynamical nuclear spin polarisation has recently been applied to enhance MRI protocols (Kurhanewicz, J., et al., Neoplasia 13, 81 (2011)). Nuclear spins associated with the C carbon isotope (nuclear spin I = 1/2) in diamond possess uniquely long spin lattice rela...

We have measured the spin polarisation of electrons scattered superelastically from laser-excited Na atoms at a collision energy of 20 eV and a scattering angle of 30’. The measured spin polarisation is 0.095 zt0.048 for scattering from the 3p zPl/z excited state of Na. The polarisation changes sign if the laser is tuned to the 3p 2P3,z state, as is expected on formal grounds. We also present c...

In this work we present a theoretical study of the effect of disorder on spin polarisation at the Fermi level, and the disorder formation energies for Co₂FexMn1-xSi (CFMS) alloys. The electronic calculations are based on density functional theory with a Hubbard U term. Chemical disorders studied consist of swapping Co with Fe/Mn and Co with Si; in all cases we found these are detrimental for sp...