  One-dimensional quantized conductance is derived from the electrons in a
homogeneous electric field by calculating the traveling time of the accelerated
motion and the number of electrons in the one-dimensional region. As a result,
the quantized conductance is attributed to the finite time required for
ballistic electrons to travel a finite length. In addition, this model requires
no Joule heat dissipation, even if the conductance is a finite value, because
the electric power is converted to kinetic energy of electrons. Furthermore,
the relationship between the non-equilibrium source-drain bias $V_\mathrm{sd}$
and wavenumber $k$ in a one-dimensional conductor is shown as $k \propto
\sqrt{V_\mathrm{sd}}$. This correspondence accounts for the wavelength of the
coherent electron flows emitted from a quantum point contact. Furthermore, it
explains the anomalous $0.7 \cdot 2e^2/h$ ($e$ is the elementary charge, and
$h$ is the Plank's constant) conductance plateau as a consequence of the
perturbation gap at the crossing point of the wavenumber-directional-splitting
dispersion relation. We propose that this splitting is caused by the Rashba
spin-orbit interaction induced by the potential gradient of the quantum well at
quantum point contacts.
