850 nm Oxide-VCSEL With Low Relative Intensity Noise and 40 Gb/s Error Free Data Transmission

We have designed and fabricated a high speed 850 nm oxide-confined vertical cavity surface emitting laser with an oxide aperture dimension of ~ 4 μm and a threshold current ITH=0.53 mA at room temperature (20 ^°C). It demonstrates a modulation bandwidth of 21.2 GHz, and achieves a laser relative intensity noise reaching standard quantum limit 2hν/P₀=-154.3 dB/Hz at high bias I/I_TH=10. Furthermore, error-free data transmission at 40 Gb/s is obtained at I=6.5 mA which corresponds to an energy/data efficiency of 431 fJ/bit.