Compact fiber-coupled terahertz spectroscopy system pumped at 800 nm wavelength

Abstract

Photonic terahertz (THz) technology using femtosecond (fs) lasers has a great potential in a wide range of applications, such as non-destructive testing of objects or spectroscopic identification of chemical substances. For industrial purposes, a THz system has to be compact and easily implementable into the particular application. Therefore, fiber-coupled THz systems are the key to a widespread use of THz technology. In order to have flexible THz emitters and detectors near infrared fs light pulses have to be sent through optical fibers of considerable length. As a consequence, the fiber's dispersion has to be compensated for and nonlinear effects in the fiber have to be minimized. A fiber-based THz time-domain spectroscopy system of high stability, flexibility, and portability is presented here.

High Resolution Waveguide Terahertz Time-Domain Spectroscopy

“…On the industrial side, the acceptance of this technique goes along with the commercialization of THz-TDS systems [72] and the integration of PPWG to entire sensors. This involves fast data acquisition at a high spectral resolution and a fast automatization of the sample changing procedure.…”

Markets, Availability, Notice, and Technical Performance of Terahertz Systems: Historic Development, Present, and Trends

“…All or partial fibercoupled optical terahertz systems will gradually replace free-space setups [52][53][54][55].…”

Applications of Terahertz Spectroscopy in the Field of Construction and Building Materials

“…Industrial applications require low-cost, easyto-use, portable systems that are still compact and reliable. Modern fiber lasers and fibercoupled detectors and emitters have enable the development of flexible, robust, and portable fiber-coupled THz TDS (62,63), which can be easily implemented to online monitoring in industry. There already exist portable battery-powered handheld THz spectrometers that allow NDT to be performed in various environmental settings (76).…”

“…Thus, nondestructive quality control to optimize the production process or detect defective parts is becoming more and more demanding. Recently, THz technology has shown great potential for inspection of various composites on the surface and inside, including in carbon-fiber composites (25,59), wood plastic composites (19), glass-fiber composites (60), polyethylene fiber composites (61), and polymer nanocomposites (29,62).…”