Dissipative optical Bloch waves

Abstract

We show that nonlinear optical cavities under periodic modulations can exhibit dissipative Bloch waves. This can be achieved by a proper choice of the incident field in the cavity that must both compensate for losses and match with the modulation period. Dissipative Bloch waves, unlike their conservative counterparts, spontaneously emerge in the cavity and hence correspond to attracting solutions. This makes it possible to experimentally visualize the band structure of the cavity medium. As an illustration of this phenomenon, we performed our analytical investigations on a degenerate optical parametric oscillator with a modulated transverse refractive index.