Applied Optoelectronics unveils 50Gbps PAM-4 directly modulated lasers

Applied Optoelectronics Inc (AOI) of Sugar Land, near Houston, TX, USA – a manufacturer of fiber-optic access network products (including components, modules and equipment) for the Internet datacenter, cable broadband, fiber-to-the-home (FTTH) and telecom markets – has developed uncooled 50Gbps PAM-4 directly modulated lasers (DMLs) for its 200Gbps and 400Gbps optical transceivers.

The 50Gbps-per-channel lasers are produced using AOI’s in-house combination of metal-organic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE) crystal growth techniques. The lasers feature high bandwidth, high linearity, and low noise (all critical for demanding applications like 200Gbps and 400Gbps transceivers). The new lasers have demonstrated a high extinction ratio of up to 6dB and a highly desirable transmitter dispersion eye closure quaternary (TDECQ) value of less than 2.5dB. All four standard coarse wavelength division multiplexing (CWDM) channels (including 1270nm, 1290nm, 1310nm and 1330nm wavelengths) have achieved data transmission over single-mode fiber lengths of 10km. The lasers are suitable in the production of 200G and 400G FR8 transceivers that meet the IEEE 802.3 200G/400G Ethernet transceiver standards.

“Transceivers based on directly modulated lasers are preferable in datacenters due to their low power consumption and low cost,” says Dr Fred Chang, senior VP & general manager of North America. “The high linearity and low noise of our 25 GBaud DML is the key to make 50Gbps per channel possible,” he adds. “With this laser, leveraging our high-volume, high-yield 100G transceiver platform, AOI is able to continue the technological and cost leadership that is of paramount importance to our hyperscale datacenter customers.”

AOI will present more details on the lasers in a presentation on 20 September at the 43rd European Conference on Optical Communication (ECOC 2017) in Gothenburg, Sweden (17-21 September), where the firm is also exhibiting in booth #538.