Efficient double intracavity-contacted vertical-cavity surface-emitting lasers with very low-threshold and low-power dissipation designed for cryogenic applications

Efficient continuous wave operation of oxide-confined double intracavity-co ntacted InGaAs-GaAs vertical-cavity surface-emitting lasers (VCSEL's) with low-threshold voltage, low-threshold current and low-power dissipation has been achieved over a wide range of cryogenic temperatures (77 K-250 K), Low operating voltages were obtained by routing current through two intracavit y contacts to bypass both distributed Bragg reflector (DBR) mirrors, while lower optical losses were achieved by using undoped DBR mirrors with abrupt heterointerfaces. This resulted in low operating voltages (<1.5 V), submil liampere threshold currents (I-th similar to 0.15 mA), low-power dissipatio n (similar to 0.21 mW at threshold) and a high power conversion efficiency (eta(eff) = 31%).