A nonlinear parametric interaction is found in the magnetoplasma in a semiconductor. The spatial asymmetry is produced by the magnetic field in the Voigt configuration, where the Lorentz force acts on the drifting electrons. The nonpolar semiconductor can be used as the nonlinear optical element. The optical parametric conversion and the second‐harmonic generation are discussed. The device operates in the infrared range. The efficiencies are found to be much larger than in conventional nonlinear optical crystals. ©1995 American Institute of Physics.