All-Optical Flip-Flop Operation at 1-mA Bias Current in Polarization Bistable Vertical-Cavity Surface-Emitting Lasers With an Oxide Confinement Structure

Polarization bistable vertical-cavity surface-emitting lasers (VCSELs) with an oxidation confinement structure were fabricated for low power consumption operation. Threshold current of the VCSEL was reduced to 0.22 mA. The VCSEL operated in a single longitudinal and transverse mode and in one of two orthogonal linear polarization modes. All-optical flip-flop operation based on polarization bistability was achieved at a record low bias current of 1.15 mA, which is about one tenth of our previously developed polarization bistable VCSEL without a current confinement structure.