Enhancement of optical second harmonic generation by utilizingthe dispersion of air

Abstract

The dispersion of air, which causes a phase shift of 27.4°/cm between optical waves at 1.06 and 0.53 μ, has been used to compensate for phase shifts between the fundamental and second harmonic in a two-pass second harmonic generation experiment. Use of this dispersion enables the net phase shift to be adjusted to zero, doubling the effective interaction length of the nonlinear crystal. The extension of this technique to multiple-pass experiments is discussed, and applications to internal harmonic generation are treated. © 1971 The American Institute of Physics.