1.3 μm Quantum Dot-Distributed Feedback Lasers Directly Grown on (001) Si

摘要

Distributed feedback (DFB) lasers represent a central focus forwavelength-division-multiplexing-based transceivers in metropolitannetworks. Here, the first 1.3 μm quantum dot (QD) DFB lasers grown on acomplementary metal-oxide-semiconductor (CMOS)-compatible (001) Sisubstrate are reported. Temperature-stable, single-longitudinal-modeoperation is achieved with a side-mode suppression ratio of more than 50 dBand a threshold current density of 440 A cm~(−2). A single-lane rate of 128 Gbits~(−1) with a net spectral efficiency of 1.67 bits~(−1) Hz~(−1) is demonstrated, with anaggregate total transmission capacity of 640 Gbit s~(−1) using five channels inthe O-band. Apart from the QD active region growth, the overall fabrication isessentially identical to the commercial process for quantum well (QW) DFBlasers. This provides a process-compatible path for QD technology intocommercial applications previously filled by QW devices. In addition, thecapability to grow laser epi across entire CMOS-compatible (001) Si wafersadds extra benefits of reduced cost, improved heat dissipation, andmanufacturing scalability. Through direct epitaxial integration of Ⅲ–Vs and Si,one can envision a revolution of the photonics industry in the same way thatCMOS design and processing revolutionize the microelectronics industry.This is discussed from a system perspective for on-chip optical interconnects.