Today, in the face of ever increasing communication traffic, minimizing power consumption in data communication systems has become a challenge. Direct modulation of lasers, a technique as old as lasers themselves, is known for its high energy efficiency and low cost. However, the modulation bandwidth of directly modulated lasers has fallen behind those of external modulators. In this Article, we report wide bandwidths of 65–75 GHz for three directly modulated laser design implementations, by exploiting three bandwidth enhancement effects: detuned loading, photon–photon resonance and in-cavity frequency modulation–amplitude modulation conversion. Substantial reduction of chirp (α < 1.0) as well as isolator-free operation under a reflection of up to 40% are also realized. A fast data transmission of 294.7 Gb s⁻¹ over 15 km of a standard single-mode fibre in the O-band is demonstrated. This was achieved without an optical fibre amplifier due to a high laser output power of 13.6 dBm.

如今，面对不断增长的通信流量，如何最大限度地降低数据通信系统的功耗已成为一项挑战。直接调制激光器是一种与激光器本身一样古老的技术，以其高能效和低成本而著称。但是，直接调制激光器的调制带宽已经落后于外部调制器。在本文中，我们通过利用三种带宽增强效应：失谐负载，光子-光子共振和腔内频率调制-振幅调制转换，报告了三种直接调制的激光器设计实现的65-75 GHz的宽带宽。还可以实现大幅降低线性调频脉冲（α  <1.0）以及在高达40％的反射率下实现无隔离器操作。294.7 Gb s的快速数据传输演示了在O波段中超过15 km的标准单模光纤^-1。由于没有13.6 dBm的高激光输出功率，因此无需使用光纤放大器即可实现这一点。