Single-shot coherent detection of terahertz pulse with broadband spectral coverage

A new scheme using centrosymmetric materials as sensor medium is presented for the single-shot coherence detection of terahertz pulse. The method relies on the electric-field-induced optical second-harmonic generation with linearly chirped optical probe pulse in centrosymmetric medium. The terahertz field is encoded onto the frequency spectrum of the second-harmonic pulse and then decoded with appropriate retrieval algorithm. This approach provides a broadband coherent spectroscopic measurement that can cover the entire terahertz gap and has transform-limited temporal resolution, which is mainly limited by the spectral bandwidth of the optical probe pulse. It can be used widely in the experiments of high field plasma physics and the diagnostics of warm dense plasmas. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3125309]