Journal ArticleWidely tunable room temperature semiconductor terahertz sourceLu, Q Y; Slivken, S; Bandyopadhyay, N; Bai, Y; Razeghi, M<p>We present a widely tunable, monolithic terahertz source based on intracavity difference frequency generation within a mid-infrared quantum cascade laser at room temperature. A three-section ridge waveguide laser design with two sampled grating sections and a distributed-Bragg section is used to achieve the terahertz (THz) frequency tuning. Room temperature single mode THz emission with a wide tunable frequency range of 2.6–4.2 THz (∼47% of the central frequency) and THz power up to 0.1 mW is demonstrated, making such device an ideal candidate for THz spectroscopy and sensing.</p>AIP Publishing2014-11-1710596301Applied Physics Letters105200003-6951https://doi.org/10.1063/1.49022452149908National Science Foundation