title: Transverse modulational instability of counterpropagating quasi-phase-matched beams in a quadratically nonlinear medium.
abstract: We find the threshold and the generation angle for transverse instability of quasi-phase-matched counter-propagating fundamental and second-harmonic beams in a bulk c((2)) medium. Numerical estimates indicate that the instability should be observable with currently available materials.
authors: P M
authors: PM
authors: Lushnikov
authors: P
authors: P
authors: Lodahl
authors: M
authors: M
authors: Saffman