  We study electron transport in quasi-one-dimensional wires at relatively weak
electrostatic confinements, where the Coulomb interaction distorts the ground
state, leading to the bifurcation of the electronic system into two rows.
Evidence of finite coupling between the rows, resulting in bonding and
antibonding states, is observed. At high dc source-drain bias, a structure is
observed at 0.5(2e^2/h) due to parallel double-row transport, along with a
structure at 0.25(2e^2/h), providing further evidence of coupling between the
two rows.
