Spectrum Shaping Of Broadband THz And Influence Of Kerr Effect To THz Detection

Terahertz time-domain spectrometry (THz-TDS) based on optical rectification is an effective phase-coherent photometric method by which one can directly measure the time-resolved electric-field both amplitude and phase of a subpicosecond THz radiation pulse generated by the mode-locked femtosecond pulse laser. At present, this technology is playing a more and more important role in many research fields. In this dissertation, some experimental research of THz is developed based on THz-TDS system. The main works are classified as follows:1. The most recent results of THz science and technology were reviewed.2. The principle of generating and detecting THz radiation is introduced.3. Using the homemade Self-mode-locked Ti: sapphire femtosecond pulse laser as a pump source,a THz Michelson interference setup based on THz-TDS is built. Using the setup, spectrum shaping based on the principle of interference is investigated in detail.4. Kerr nonlinearity and Kerr-like nonlinearity induced by femtosecond pulses via terahertz generation and electro-optical effect are investigated. A method to distinguish the two signals experimentally is proposed.