新世代光纖載微波系統與技術之整合研究-子計畫七：高重複率低雜訊鎖模光纖雷射光源與其微波光電和量子應用之研究

Abstract

本子計畫將發展新穎高重複率低雜訊鎖模光纖雷射來作為光纖載微 波通訊、微波光電、量子光學等應用之光源。透過創新非同步分數諧波鎖 模光纖光固子雷射技術的發展，我們預期可以產生脈衝重複率為電驅動頻 率整數倍的飛秒級光脈衝序列，而且可以避免原有同步分數諧波鎖模光纖 雷射脈衝振幅不均勻的缺點，以及克服高重複率鎖模光纖雷射共振腔長回 饋控制上的高頻電子技術困難。此種高重複率鎖模光纖雷射將可直接用來 作為超短脈衝光源以產生寬頻微波信號，或是透過光學濾波來產生窄頻微 波信號。此種高重複率鎖模光纖雷射穩定後也可用來作為光梳頻光源，透 過光學濾波適當取出光頻分量再將微波信號調變其上即能來作為光纖載 微波通訊所需的信號源，或是用來作為發展新穎微波光電信號處理技術的 光源。本子計畫中我們也將進一步探討非同步鎖模光纖雷射的雜訊機制， 希望能透過種種鎖定的方法來儘可能降低非同步鎖模光纖雷射的功率、時 序、與相位雜訊，以期能進一步來發展其在精密光電信號產生、傳輸、及 量測等方面應用。這種低雜訊鎖模光纖雷射也有機會可以用來作為量子光 學研究的光源，用來產生特殊之量子糾結態光，然後利用這種新的量子糾 結態光來發展量子通訊等方面的可能應用。

The main focus of the present project is to investigate new types of high repetition rate low noise modelocked fiber lasers for the possible applications of Radio-over-Fiber communication, microwave photonics, and quantum optics. The novel asynchronous rational harmonic modelocked fiber lasers to be developed can multiply the laser pulse repetition rate without the shortcoming of un-equal pulse amplitude and the difficulty of cavity length feedback control in comparison to traditional rational harmonic modelocked fiber lasers. This type of high repetition rate modelocked fiber lasers can be directly used to generate broadband microwave signals with a fast detector or to generate narrowband microwave signals through optical filtering first. As one type of optical frequency comb laser sources, the modelocked fiber lasers can also be used as the light sources for Radio-Over-Fiber communication through the use of optical filtering and signal encoding. They can also be the suitable laser sources for microwave photonic signal processing. We will also investigate the noise mechanisms of asynchronous modelocked fiber lasers and try to reduce their energy, jitter, and phase noises so that they can be suitable for applications of precision signal generation, transmission, and measurement. These high repetition rate low noise modelocked fiber lasers may also be used for generating and detecting new entangled lights in the area of quantum optics and quantum communication.