Compact fiber pumped terahertz source

Abstract

Converting near infrared signals in a nonlinear medium is an attractive way to generate terahertz radiation due to the availability of near-IR lasers and nonlinear materials. However, these terahertz generation schemes are typically inefficient and are often cumbersome, which may limit their use in certain applications. We have developed and demonstrated a compact, fiber pumped optical terahertz source based difference frequency mixing (DFM) of nanosecond pulses in zinc germanium phosphide (ZGP). With this setup, we have successfully generated 2mW of average power terahertz radiation at 2.45THz. This has enabled us to perform active, real-time terahertz imaging experiments using an uncooled microbolometer array. In performing these experiments, we have also developed a theoretical model for terahertz generation based on DFM of IR pump signals. In this paper, we discuss our compact fiber pumped terahertz source technology, imaging system, model, and how we intend to overcome some of the common issues associated with optical terahertz generation.