We present an experimental demonstration of an optical flip–flop based on two-mode intensity bistability in a GaAs/AlGaAs cross-coupled bistable laser diode (XCBLD), in which lasing can be toggled between two orthogonal outputs. Electrically triggered set–reset optical memory operation has been achieved in a folded-cavity device under pulsed bias at 77 K. The XCBLD is monolithically integrable and has extensive applications in optical time-division switching.