Design and applications of a THz polarizing beamsplitter

• Main Authors: Kao, Yung Cheng, 高永成
• Other Authors: Chuu, Chih Sung
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/96059807796210348776

碩士 === 國立清華大學 === 物理系 === 103 === It has been a great interest to control and manipulate THz wave due to its unique properties and various applications. In the emerging field of THz quantum optics, for example, one will need to split an incident THz wave in order to study the photon statistics. However, THz polarizing beam splitters are still rarely available on the market. The purpose of this thesis is thus to develop a THz polarizing beamsplitter using accessible materials. Inspired by an earlier theoretical work, we demonstrate a low-cost narrowband polarizing beamsplitter in the THz region. The beamsplitter is composed of alternating layers of paper and air. The incident THz beam, generated by exciting a biased semiconductor antenna with a femtosecond laser pulse, is tilted at a Brewster angle with respect to the first layer. We characterize the performance of the beamsplitter by terahertz time-domain spectroscopy. We also use genetic algorithm to propose a broadband THz beamsplitter.