Abstract
We show theoretically that the waves generated through the generic parametric three- or four-wave-mixing processes exhibit, as a general rule, a hidden coherence characterized by skewed coherence lines along specific space-time trajectories. Our study generalizes the concept of coherence in the sense that these previously unrecognized coherent states cannot be described through the standard definitions of spatial and temporal coherence.
- Received 24 September 2001
DOI:https://doi.org/10.1103/PhysRevLett.88.083901
©2002 American Physical Society