Density dependent spin polarisation in ultra low-disorder quantum wires
  There is controversy as to whether a one-dimensional (1D) electron gas can spin polarise in the absence of a magnetic field. Together with a simple model, we present conductance measurements on ultra low-disorder quantum wires supportive of a spin polarisation at B=0. A spin energy gap is indicated by the presence of a feature in the range 0.5 - 0.7 X 2e^2/h in conductance data. Importantly, it appears that the spin gap is not static but a function of the electron density. Data obtained using a bias spectroscopy technique are consistent with the spin gap widening further as the Fermi-level is increased. 
D. J. Reilly, T. M. Buehler, J. L. O'Brien, A. R. Hamilton, A. S.   Dzurak, R. G. Clark, B. E. Kane, L. N. Pfeiffer and K. W...