Density-dependent spin polarization in ultra-low-disorder quantum wires.
There is controversy as to whether a one-dimensional (1D) electron gas can spin polarize 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 polarization at B=0. A spin energy gap is indicated by the presence of a feature in the range (0.5-0.7)x2e(2)/h in conductance data. Importantly, it appears that the spin gap is not constant 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.
Reilly
D J
DJ
Centre for Quantum Computer Technology, University of New South Wales, Sydney 2052, Australia. djr@jupiter.phys.unsw.edu.au
Buehler
T M
TM
O'Brien
J L
JL
Hamilton
A R
AR
Dzurak
A S
AS
Clark
R G
RG
Kane
B E
BE
Pfeiffer
L N
LN
West
K W
KW