LOW-TEMPERATURE BEHAVIOR OF LASER-DIODES

Low temperature behaviour of InGaAsP laser diode is studied. The laser is a Fabry-Perot type with a Buried Heterostructure. A large improvem ent of threshold current is obtained as the temperature decreases. The exponential variation of Ith is verified and a T0 value of 69K is ded uced. The intrinsic resonant frequency is measured with noise analysis . This resonance varies as the square root of the net injected current . The slopes of these curves are found to increase dramatically with d ecreasing temperature. The 3 dB bandwidth experiments are also perform ed, leading in the same way, to a large increase of the slopes with co oling but package parasitics limit the maximum achievable bandwidth. T he influence of the laser parasitics, such as the roll-off phenomenum, is also underlined.