G. Goncher et al., CRYOGENIC OPERATION OF ALGAAS-GAAS VERTICAL-CAVITY SURFACE-EMITTING LASERS AT TEMPERATURES FROM 200 K TO 6 K, IEEE photonics technology letters, 8(3), 1996, pp. 316-318
We demonstrate for the first time the CW performance of AlGaAs-GaAs ve
rtical-cavity surface-emitting lasers (VCSEL's) at cryogenic temperatu
res from 6 K to 200 K, By detuning the cavity mode with respect to the
gain peak so that optimum de lasing operation is achieved at similar
to 100 K, we find that this optimum lasing performance can be maintain
ed down to temperatures as low as 6 K. Across a broad range of tempera
tures from 200 K to 6 K, the minimum threshold current of a 16-mu m di
ameter VCSEL stayed below 4 mA, while its -3-dB modulation bandwidth i
ncreased by about 70% to 11 GHz at 6 K, and the external slope efficie
ncy is greater than 70%.