在不同溫度下自動調變波長之可撓式微共振腔雷射

Abstract

近年來，光子晶體結構已被大量發展在各種光學應用上，可應用於光通訊的可調式半導體雷射更是一個重要的研究課題，藉由微調光子晶體的幾何結構，可得到特定的雷射波段以及操作模態。因此，我們使用軟性有機聚合物材料作為基板所製作的光學元件可使之有可撓的特性，並能直接藉由外力調整幾何結構來獲得所需的雷射波長，然而，還是存在著其他因素會稍微影響著半導體雷射的波長，例如溫度、注入載子濃度以及製程缺陷等等，就光通訊的運用而言，可能造成訊號傳輸過程中錯誤的訊號。因此，為了進行進一步的實際應用，我們在這篇論文中提出解決方案，當波長隨著溫度上升而造成紅移時，我們所設計的自動調變系統將會使用外力來調整元件的幾何結構，進而造成波長的藍移來補償錯誤，由其結果來看，可撓式的雷射元件將會擁有自我固定波長的能力，藉由這個概念的延伸，可以預期之後的發展上，可撓式的雷射元件將可忽略任何干擾。

In recent years, the photonic crystal structures have been widely developed for a variety of optical applications. One of the important researches is the tunable semiconductor laser in optical communications. By fine tuning the geometry structure of the photonic crystals, specific wavelengths and operation modes could be obtained. Therefore, soft organic polymer materials are used as the substrate which could have the flexible ability to adjust the structure by external force for an optical device. With the ability, the required lasing wavelength could be obtained easily. However, there still exist some factors which affect the lasing wavelength of semiconductor laser slightly such as temperature, injected carrier concentration, and defect from fabrication. In terms of optical communications, it may result in an error signal in transmission process. Therefore, in order to conduct further practical application, we are here proposing a solution in this thesis: while the lasing wavelength redshifts with the ambient temperature increasing, the designed auto-tuning setup would make the wavelength blueshift by external force to compensate the error. As a result, the flexible laser device would have the ability to fix the lasing wavelength itself. By extending this concept, it is assumed that any perturbations which affect the lasing wavelength could be ignored.