Science Daily January 26, 2022
Despite decades of research, no frequency tunable sources span the terahertz gap between 0.3 and 3 THz. By introducing methyl fluoride (CH3F) as a new gain medium for a quantum cascade laser-pumped molecular laser (QPML), a team of researchers in the US (Harvard University, industry, DEVCOM ARL, Duke University) has demonstrated continuous-wave lasing from more than 120 discrete transitions, spanning the range from 0.25 to 1.3 THz. Due to its large permanent dipole moment and large rotational constants, methyl fluoride (CH3F) as a QPML gain medium combines a lower threshold, a larger power efficiency, and a wider tuning range than other molecules. These key features of the CH3F QPML, operated in a compact cavity at room temperature, pave the way to a versatile THz source to bridge the THz gap… read more. Open Access TECHNICAL ARTICLEÂ
Schematic of the experimental setup… Credit: APL Photonics, Volume 7, Issue 1,january 25, 2022Â