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 <i>c</i><sup>(2)</sup> medium. Numerical estimates indicate that the instability should be observable with currently available materials.
© 1998 America
P. M. Lushnikov, P. Lodahl, and M. Saffman, "Transverse modulational instability of counterpropagating quasi-phase-matched beams in a quadratically nonlinear medium," Opt. Lett. 23, 1650-1652 (1998)