Single Quantum-Well Transistor Lasers Operating Error-Free at 22 Gb/s

Abstract

Data are presented showing error-free transmission by a 200- $\mu $ m-long transistor laser at 15 °C. The device has a threshold current of 30 mA and exhibits a modulation bandwidth of $f_{\mathbf {-3dB}} = 10.4$ GHz at I $_{B}= 85$ mA and V $_{\mathrm {\mathbf {CE}}} = 1.5$ V. At this bias point, the device is able to transmit $2^{7}$ -1 Pseudo Random Binary Sequence (PRBS) data with no errors at 22 Gb/s. The effect of transistor laser input impedance on optical modulation amplitude is discussed and short cavity ( $200~\mu $ m) devices are shown to exhibit a better match to the 50 $\Omega $ impedance of the signal generator.