All-optical analog comparator.
All-optical analog comparator.
复制标题
全光模拟比较器
DOI：
10.1038/srep31903
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发表时间：
2016-08-23
影响因子：
4.6
通讯作者：
Wang Y
中科院分区：
文献类型：
--
作者：
Li P;Yi X;Liu X;Zhao D;Zhao Y;Wang Y
模拟比较器是全光模数转换(AO-ADC)系统的核心部件之一，它通过与已定义的判决门限进行比较，将不同的幅度电平数字化为两个逻辑‘1’或‘0’电平。虽然已经报道了各种优秀的光子ADC方法，但几乎所有的方法都需要一个电子比较器来执行这种二值化。使用电子比较器与开发全光学器件的目标相矛盾。在这项工作中，我们提出了一种全光模拟比较器的新概念，并数值演示了一种基于具有多量子阱(MQW)结构的四分之一波长移位分布反馈激光二极管(QWS DFB-LD)的实现。结果表明，该全光比较器非常适合于真正的声光模数转换器，能够实现从模拟光信号(连续时间信号或离散脉冲信号)到完全在光域中的二进制表示的全数字转换。该全光模拟比较器具有低的阈值功率(几mW)、高的消光比(高达40 分贝)、高的运算速率(数十Gb/S数量级)和阶梯形的传递函数。
An analog comparator is one of the core units in all-optical analog-to-digital conversion (AO-ADC) systems, which digitizes different amplitude levels into two levels of logical ‘1’ or ‘0’ by comparing with a defined decision threshold. Although various outstanding photonic ADC approaches have been reported, almost all of them necessitate an electrical comparator to carry out this binarization. The use of an electrical comparator is in contradiction to the aim of developing all-optical devices. In this work, we propose a new concept of an all-optical analog comparator and numerically demonstrate an implementation based on a quarter-wavelength-shifted distributed feedback laser diode (QWS DFB-LD) with multiple quantum well (MQW) structures. Our results show that the all-optical comparator is very well suited for true AO-ADCs, enabling the whole digital conversion from an analog optical signal (continuous-time signal or discrete pulse signal) to a binary representation totally in the optical domain. In particular, this all-optical analog comparator possesses a low threshold power (several mW), high extinction ratio (up to 40 dB), fast operation rate (of the order of tens of Gb/s) and a step-like transfer function.