TRANSVERSE PATTERNS IN NASCENT OPTICAL BISTABILITY

We study the Swift-Hohenberg equation describing a passive optical cav ity driven by an external coherent field, valid close to the onset of optical bistability. A linear analysis shows that the system can susta in nontrivial stationary structures for small positive detunings. A we akly nonlinear analysis in the vicinity of the instability points reve als the existence of stable hexagonal structures which eventually give way to rolls. Numerical simulations support such a bifurcation scenar io.