Fig. 2

a-d Dependence of a velocity υ′_z (z - component) of a nonrelativistic electron on the phase of an electric field. The conditions are the same with in Fig. 1a-d, except for the following two changes: \( \left\{\begin{array}{c}{c}^{"}={\left(3\times {10}^8\ \mathrm{m}/\sec \right)}^2\to {\left(3\times {10}^8\times {10}^6\ \mathrm{m}/\sec \right)}^2\\ {}\kern0.5em t={t}_0\sim {t}_0+12\ \left(2\uppi /{\omega}_c\right)\to \kern0.5em t={t}_0\sim {t}_0+24\ \left(2\uppi /{\omega}_c\right)\ \sec \end{array}\right. \) Every relativistic effect in Eq. (12) is acompanied by the factor \( {z}_0^2/{c}^{"} \). So, we obtain nonrelativistic characteristics by setting c^" to (3 × 10⁸ × 10⁶ m/sec)², from now