未來光通訊系統所需之新穎光電元件與技術之研究---子計畫五：新穎光固子光纖雷射光源及其在量子通訊等方面之應用

Abstract

本研究計畫將研究新型的鎖模光纖光固子雷射及其在量子通訊等方 面的可能應用。光纖中的非線性光固子效應具有相當獨特的一些性質，可 以用來作長距離訊號傳輸，也可用來作為光纖雷射的鎖模機制來產生超短 光脈衝。最近的一個發展趨勢是利用鎖模光纖雷射來作為光固子的實驗平 台，在其上來研究新的光固子效應。隨著高功率光纖放大器的普及，光纖 雷射的輸出功率也能夠越來越大，這使得光纖雷射可以應用的範圍也越來 越大。配合著新型高非線性光纖的普及，如今要在光纖中利用非線性效應 來進行古典與量子光學實驗的可行性也越來越容易。在諸多鎖模光纖雷射 的可能應用中，量子通訊方面的應用最近在學術上受到很大的重視，特別 是以量子密碼傳輸為主的相關研究領域。量子密碼傳輸可以用幾種不同的 方法來達到，在本計畫中我們想要探討的是如何利用鎖模光纖光固子雷射 及光纖中的非線性光固子效應來產生量子糾結態光，然後又可以如何利用 此種特殊的光固子量子糾結態光來達到量子密碼傳輸的應用目的。除了量 子通訊的應用外，我們也將更深入探討鎖模光纖光固子雷射的雜訊特性以 求能製作出低雜訊的雷射光源來進行量子效應的實驗，同時也將探討光固 子慢光效應的量子特性以求能找出更有效的機制來產生新的量子態光並 發展新的未來光通訊應用。

The main focus of the present project is to investigate new types of modelocked fiber soliton lasers and to develop their possible applications in the area of quantum communication, etc. The nonlinear soliton phenomena in optical fibers have some unique properties. They can be used for long distance optical transmission and also for building modelocked fiber lasers that can output ultrashort optical pulses. Another recent trend is to investigate new type of soliton phenomena based on the modelocked fiber soliton laser platform. With the availability of high power fiber amplifiers, the output powers of fiber lasers are increased and the applications of fiber lasers also get increased a lot. In particular, also with the availability of the highly nonlinear optical fibers, it is now easier to utilize the fiber nonlinearity for performing classical or quantum optical experiments. Among the possible applications, the quantum communication area has attracted a lot of research focus recently, especially for the quantum key distribution applications. Several approaches have been developed to achieve the quantum key distribution purpose. The present project will focus on how to generate entangled lights from modelocked fiber soliton lasers and from the soliton phenomena in optical fibers. Then we will investigate how to utilize these new quantum lights for achieving the quantum key distribution purpose. Besides the applications of quantum communication, we will also investigate the noise properties of modelocked fiber soliton lasers with the aim to build low-noise laser sources suitable for quantum applications, and explore the quantum properties of soliton slow light phenomena with the aim to find new mechanisms for generating new quantum lights and for developing new optical communication applications.