Raman source using a hollow-core fiber for ozone monitoring in the lower troposphere

Abstract. The DIfferential Absorption microlidar for Boundary Layer Ozone (DIABLO) is designed for boundary-layer profiling. This instrument uses a diode-pumped, passively Q-switched Nd:YAG laser at 266 nm, coupled to a deuterium-filled hollow-core fiber (HCF) to generate the 289 nm Stokes wavelength via stimulated Raman scattering (SRS). The high Raman gain in the gas-filled HCF enables efficient UV conversion with significantly lower pump energy than required in traditional free-space Raman cells. At the output of the fiber, 1-ns pulses of 10 μJ at 266 nm and 7 μJ at 289 nm are obtained with a repetition rate of 1 kHz. First atmospheric measurements in central Paris provide ozone concentrations between 400 m and 1700 m. In contrast with existing UV DIAL ozone systems, which are typically bulky, complex, and operated in campaign-based research configurations, DIABLO targets a compact and low-energy architecture optimized for autonomous boundary-layer monitoring.