학술논문
Monolithic InAs/InP Quantum Dash Mode-Locked Lasers for Millimeter-Wave-Over-Fiber Mobile Fronthaul Systems
Document Type
Periodical
Author
Source
IEEE Journal of Selected Topics in Quantum Electronics IEEE J. Select. Topics Quantum Electron. Selected Topics in Quantum Electronics, IEEE Journal of. 29(6: Photonic Signal Processing):1-10 Jan, 2023
Subject
Language
ISSN
1077-260X
1558-4542
1558-4542
Abstract
Semiconductor monolithic mode-locked lasers (MLLs) are potential solutions for generating high-speed optical pulses in future mobile fronthaul networks in the millimeter-wave (mmW) bands. Our previous studies have investigated using buried heterostructure (BH) quantum dash (QDash) multi-wavelength lasers for photonic mmW applications. Here we present results from monolithic chip-scale ridge waveguide QDash MLLs for generating and transmitting mmW signals. Through optimizing epitaxy growth, waveguide design, and fabrication process, the five-layer ridge waveguide QDash MLL exhibits superior performance with regard to the coherent comb bandwidths, lasing threshold current, output power, and internal quantum efficiency. The generated mmW frequency at 28.36 GHz exhibits excellent frequency stability, with a drift of less than ±50 kHz. For the first time, we have utilized the free-running five-layer ridge waveguide QDash MLL to implement single- and dual-optical carrier modulation schemes in the millimeter-wave-over-fiber (mmWoF) systems. Both modulation schemes have achieved satisfactory performance achieving error vector magnitude (EVM) performance much lower than the 3GPP requirements (