Widely Tunable Terahertz‐Generating Semiconductor Disk Laser

Abstract: The demand for tunable terahertz (THz) generating laser sources is significantly growing as they are used in a wide range of applications including THz imaging, spectroscopy, and metrology. However, the development of THz systems for the use in many practical applications is generally impeded by the limited availability of compact, sufficiently powerful and cost‐effective room‐temperature sources in the desired spectral ranges. Herein, the development of a compact, continuous‐wave, room‐temperature, tunable THz‐generating laser source in the 0.79–1.11 THz spectral region is reported. The laser source is based on intracavity difference‐frequency generation in an aperiodically poled lithium niobate (aPPLN) crystal within a dual‐wavelength vertical‐external‐cavity surface‐emitting laser. Furthermore, spectral coverage in the THz domain is compared for such a device utilizing a periodically poled lithium niobate (PPLN) and an aPPLN crystal. The demonstrated results pave the way to an effective approach for the development of high‐performance, room‐temperature, widely tunable THz lasers for a variety of applications in science and industry.