Freeing Nonlinear Optics from Phase Matching

摘要

The advent of lasers quickly led to the demonstration of nonlinear optical effects. One of the simplest examples of a nonlinear effect is doubling the input frequency of light with a nonlinear crystal. The output intensity of the frequency-doubled light then grows nonlinearly with the intensity of the laser beam. To maximize macroscopic nonlinear signals, the wavelets emitted by the elementary nonlinear sources need to add up in phase. On page 1223 of this issue, Suchowski et al.