Download or read book A Terahertz Emission Spectrometer for the Study of Ultrafast Carrier Dynamics in Semiconductors written by Gregory Bell and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Ultrafast charge carrier dynamics in semiconductors are behind many operation characteristics of opto-electronic devices. The buildup of carrier momentum in an electric field involves more than the field itself. The buildup also depends on intrinsic interactions within a material that occur on ultrafast time scales. The acceleration of the charges that attain this momentum emit a radiation that reveals details of the carrier motion via Maxwell's equation. The frequency of these electromagnetic waves thus depends on the internal processes controlling the momentum rise. These time scales in semiconductors are often in the picosecond regime, which can lead to generation of terahertz (THz) light. By taking coherent measurements of the electric field in time, one can glean information about the carrier motion on femtosecond (fs) times scales. In this writing, the construction of time-resolved THz emission spectrometers designed to detect this THz radiation from sources biased by a quasi-static electric field while being excited by a pulsed fs laser is discussed. The theory of the THz generation from semiconductors outlined is based on established techniques, and shows how they can be used to obtain information ab out the material's properties. Theperformance of the spectrometer is established with standard electro-optic emitters ZnTe and GaP. Two attempts are made to detect THz radiation from novel systems: semiconductor quantum dots (QDs), and organo metallic halide perovskite thin films. Complications that were encountered are summarized, along with steps to overcome them, with the plan to continue to employ the current spectrometer into inquiries ab out ultrafast carrier dynamics in materials." --