The key factor in High Pressure Hydrogenotrophic Denitrification: Hydrogen partial pressure

In the envisaged hydrogen economy, H₂ could be an interesting alternative electron donor for the denitrification of drinking water or wastewater. The main obstacle to engineering the hydrogenotrophic denitrification process is the low solubility of H₂ in water under atmospheric pressure, which limits denitrification rate...

Frequency and amplitude stabilized terahertz quantum cascade laser as local oscillator

We demonstrate an experimental scheme to simultaneously stabilize the frequency and amplitude of a 3.5 THz third-order distributed feedback quantum cascade laser as a local oscillator. The frequency stabilization has been realized using a methanol absorption line, a power detector, and a proportional-integral-derivative (PID) loop. The amplitude...

Frequency locking of single-mode 3.5-THz quantum cascade lasers using a gas cell

We report frequency locking of two 3.5-THz third-order distributed feedback (DFB) quantum cascade lasers (QCLs) by using methanol molecular absorption lines, a proportional-integral-derivative controller, and a NbN bolometer. We show that the free-running linewidths of the QCLs are dependent on the electrical and temperature tuning coefficients....