Highly uniform operation of high-performance 1.3-/spl mu/m AlGaInAs-InP monolithic laser arrays

Abstract

We describe the fabrication of monolithically integrated 1/spl times/12 arrays of 1.3-/spl mu/m strain-compensated multiquantum-well AlGaInAs-InP ridge lasers. The laser array shows highly uniform characteristics in threshold current, slope efficiency, and lasing wavelength with a standard deviation of 0.08 and 0.27 mA, 0.012 and 0.007 W/A, and 0.59 and 0.57 nm, respectively, at 20/spl deg/C and 100/spl deg/C. Besides, each laser on the array exhibits a low threshold current of 8 mA at 20/spl deg/C and 21 mA at 100/spl deg/C, a characteristic temperature of 92 K, and a slope efficiency drop of 0.7 db between 20/spl deg/C and 80/spl deg/C. A low thermal crosstalk of less than -4 dB can be obtained from one diode as the injected current of other elements is increased to 70 mA. Also, each laser on the array has a negligible degradation after a 24-hr burn-in test at 80 mA and 100/spl deg/C. An expected lifetime of more than 20 years is estimated for the lasers when operating at 10 mW and 85/spl deg/C. The lasers have a small-signal modulation bandwidth of about 9 GHz at 25/spl deg/C and a low relative intensity noise of -155 dB/Hz without an isolator at 2.5 GHz. It can transmit a 2.5-GHz signal to 50 km through standard single-mode fiber and to 308 m through multimode fiber, with a clear eye opening in OC-48 data-rate tests.