Study on Ultra-Multiplexed Photonic Network Technology with Photonic Crystal

基于波分复用(WDM)的超宽带光传输系统及其全光信号处理技术是未来光网络不可缺少的组成部分。尤其是超宽带波长转换必须发挥重要作用，才能发展这样的网络。本工作的目的是利用光子晶体光纤(PCF)和半导体光放大器(SOA)实现超宽带波长转换。首先，我们研究了一种利用光子晶体光纤实现的超宽带波长转换，从理论和实验上研究了常规光子晶体光纤的波长转换特性。结果表明，用传统的光子晶体光纤很难实现工作波长范围超过60 nm的超宽带波长转换。为了实现超过100 nm的宽带波长转换，需要具有更高的非线性系数和更低的色散的特殊光子晶体光纤。其次，我们研究了…提出了一种利用传统SOA实现超宽带波长转换的新技术。该转换器由多级级联波长转换器组成，每个级联波长转换器使用不同的增益带。每个级联波长转换器使我们能够执行同相(NIV)和反相(IV)运算。根据作为转换器输入/输出功率的函数的静态特性，比较了NIV和IV操作下的转换性能。虽然两种操作都获得了良好的转换性能，但IV波长转换具有更好的级联能力，可以为级联方案获得高质量的转换信号。此外，还通过重复IV波长转换实现了信号幅度的再生。最后，我们首次成功地演示了超宽带波长转换，包括使用三级级联波长转换器将超过300 nm的波长跳跃到较短的波长侧，这些结果表明我们提出的技术将有助于提高未来超宽带光网络的灵活性。较少

Ultra-wideband optical transmission systems based on wavelength-division-multiplexing (WDM) and its all-optical signal processing techniques are indispensable for future photonic networks. In particular, ultra-wideband wavelength conversion must play an important role to develop such networks. The purpose of this work is to realize ultra-wideband wavelength conversion by utilizing photonic crystal fiber (PCF) and semiconductor optical amplifier (SOA).First, we have studied an ultra-wideband wavelength conversion using PCF We have investigated the wavelength conversion characteristics of the conventional PCF theoretically and experimentally. As a result, we have concluded that it is very difficult to realize an ultra-wideband wavelength conversion with over 60 nm wavelength operating range by using the conventional PCF. To realize over 100 nm wideband wavelength conversion, special PCF with higher nonlinear coefficient and lower chromatic dispersion will be required.Next, we have studie … More d SOA-based wavelength conversion, and proposed a novel technique to realize ultra-wideband wavelength conversion using conventional SOAs. The proposed converter consists of multistage cascaded wavelength converters using SOAs each with different gain band. Each of the cascaded wavelength converters enables us to perform both noninverted (NIV) and inverted (IV) operations. Conversion performance is compared at NIV and IV operations in terms of static characteristics as a function of input/output power of the converter. While good conversion performances are achieved at both operations, the IV wavelength conversion has better cascadability to obtain a high-quality converted signal for the cascaded scheme. Moreover, signal amplitude regeneration is demonstrated by repeating the IV wavelength conversion. Finally, we successfully demonstrate, for the first time, ultra-wideband wavelength conversion, including over 300 nm wavelength hopping to the shorter wavelength side with a triple-stage cascaded wavelength converter.These results indicate that our proposed technique will be useful in improving the flexibility of future ultra-wideband photonic networks. Less