Benzene sensing by Quartz Enhanced Photoacoustic Spectroscopy at 14.85 µm

International audienceBenzene is a gas known to be highly pollutant for the environment, for the water and cancerogenic for humans. In this paper, we present a sensor based on Quartz Enhanced Photoacoustic Spectroscopy dedicated to benzene analysis. Exploiting the infrared emission of a 14.85 µm quantum cascade laser, the sensor is working in an off-beam configuration, allowing easy alignment and stable measurements. The technique provides a very good selectivity to the sensor and a limit of detection of 30 ppbv in 1 s, i.e. a normalized noise equivalent absorption of 1.95 × 10 −8 W.cm −1 .Hz −1/2. The achieved performances of the sensor have enabled measurements on several air samples of a gas station showing a non-neglectable risk in case of long exposure

InAs-Based Quantum Cascade Lasers with Extremely Low Threshold

We report InAs-based quantum cascade lasers (QCLs) operating near 14 µm with a threshold current density Jth as low as 0.6 kA/cm2 at room temperature. The threshold obtained is lower than the Jth of the best reported InP-based QCLs to date without facet treatment. The achieved performance improvement is partially due to an increased separation between the upper transition level and the next one in the active quantum wells of the employed QCL design

Virtual reality distraction: A novel behaviour management technique

Virtual reality distraction (VRD) is developing technologies for behavior management that can assist a child in adjusting to the dental setting and provide high-quality dental care. The purpose of this literature is to shed light on VRD and its application to the treatment of pediatric dental patients

InAs-Based Quantum Cascade Lasers with Extremely Low Threshold

We report InAs-based quantum cascade lasers (QCLs) operating near 14 µm with a threshold current density Jth as low as 0.6 kA/cm2 at room temperature. The threshold obtained is lower than the Jth of the best reported InP-based QCLs to date without facet treatment. The achieved performance improvement is partially due to an increased separation between the upper transition level and the next one in the active quantum wells of the employed QCL design