Static-electric-field-induced polarization effects in harmonic generation

Two static-electric-field-induced effects on harmonic generation are demonstrated analytically and numerically: elliptic dichroism (in which the harmonic yield is different for right and left elliptically polarized laser fields) and elliptical polarization of harmonics produced by linearly polarized driving laser fields. Both effects stem from interference of real and imaginary parts of the nonlinear atomic susceptibilities. Possibilities for experimentally measuring these effects are discussed.