Cavity solitons in bidirectional lasers.

We show theoretically that a broad area bidirectional laser with slightly different cavity losses for the two counterpropagating fields sustains cavity solitons (CSs). These are complementary; i.e., there is a bright (dark) CS in the field with larger (smaller) losses. Interestingly, the CSs can be written or erased by injecting suitable pulses into any of the two counterpropagating fields.