EPSRC National Centre for III-V Technologies, Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 3JD, United Kingdom.
Sci Rep. 2012;2:477. doi: 10.1038/srep00477. Epub 2012 Jun 28.
High pulse repetition rate (≥ 10 GHz) diode-pumped solid-state lasers, modelocked using semiconductor saturable absorber mirrors (SESAMs) are emerging as an enabling technology for high data rate coherent communication systems owing to their low noise and pulse-to-pulse optical phase-coherence. Quantum dot (QD) based SESAMs offer potential advantages to such laser systems in terms of reduced saturation fluence, broader bandwidth, and wavelength flexibility. Here, we describe the development of an epitaxial process for the realization of high optical quality 1.55 µm In(Ga)As QDs on GaAs substrates, their incorporation into a SESAM, and the realization of the first 10 GHz repetition rate QD-SESAM modelocked laser at 1.55 µm, exhibiting ∼2 ps pulse width from an Er-doped glass oscillator (ERGO). With a high areal dot density and strong light emission, this QD structure is a very promising candidate for many other applications, such as laser diodes, optical amplifiers, non-linear and photonic crystal based devices.
高脉冲重复率（≥10GHz）二极管泵浦固态激光器，采用半导体可饱和吸收镜（SESAMs）锁模，由于其低噪声和脉冲间光相位相干性，正在成为高速率相干通信系统的一项关键技术。基于量子点（QD）的 SESAMs 在降低饱和通量、拓宽带宽和波长灵活性方面为这类激光系统提供了潜在的优势。在这里，我们描述了一种在 GaAs 衬底上实现高质量 1.55μm In(Ga)As QD 的外延工艺的发展，将其纳入 SESAM，并实现了首个 10GHz 重复率的 1.55μm QD-SESAM 锁模激光器，从掺铒玻璃振荡器（ERGO）中发射出约 2ps 的脉冲宽度。由于具有高面密度和强发光特性，这种 QD 结构是许多其他应用的非常有前途的候选者，例如激光二极管、光放大器、非线性和基于光子晶体的器件。
