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子网络不可缺少的技术。特别是，超宽带波长转换必须发挥重要作用，以发展这样的网络。本研究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，我们研究了利用PCF的超宽带波长转换，从理论和实验上研究了传统PCF的波长转换特性。因此，我们得出结论，使用传统的PCF很难实现超过60 nm波长工作范围的超宽带波长转换。为了实现100 nm以上的宽带波长转换，需要具有较高非线性系数和较低色散的特殊PCF。接下来，我们研究了基于soa的波长转换，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增益带的soa。每个级联波长转换器使我们能够执行非反转（NIV）和反转（IV）操作。根据静态特性作为转换器输入/输出功率的函数，比较了NIV和IV操作下的转换性能。虽然在两种操作中都获得了良好的转换性能，但IV波长转换具有更好的级联性，可以为级联方案获得高质量的转换信号。此外，通过重复IV波长转换证明了信号幅度再生。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的波长跳变到更短的波长侧。这些结果表明，我们所提出的技术将有助于提高未来超宽带光子网络的灵活性。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