Anders Brusch

A versatile integrating sphere based photoacoustic sensor for trace gas monitoring

A compact versatile photoacoustic (PA) sensor for trace gas detection is reported. The sensor is based on an integrating sphere as the PA absorption cell with an organ pipe tube attached to increase the sensitivity of the PA sensor. The versatility and enhancement of the sensitivity of the PA signal is investigated by monitoring specific ro-vibrational lines of CO(2) in the 2 μm wavelength region and of NO(2) in the 405 nm region. The measured enhancement factor of the PA signal exceeds 1200, which is due to the acoustic resonance of the tube and the absorption enhancement of the integrating sphere relatively to a non-resonant single pass cell. It is observed that the background absorption signals are highly attenuated due to the thermal conduction and diffusion effects in the polytetrafluoroethylene cell walls. This demonstrates that careful choice of cell wall materials can be highly beneficial to the sensitivity of the PA sensor. These properties makes the sensor suitable for various practical sensor applications in the ultraviolet (UV) to the near infrared (NIR) wavelength region, including climate, environmental and industrial monitoring.

Isotope shifts of the (3s3p) 3P0,1,2-(3s4s) 3S1 Mg I transitions

We report measurements of the isotope shifts of the (3s3p)

Flow immune photoacoustic sensor for real-time and fast sampling of trace gases

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Fiber-based portable optical frequency standard for telecommunication

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Compact sensor for photoacoustic monitoring and photochemical dissociation of NO2

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Towards an all fibre based optical frequency standard using acetylene-filled hollow-core photonic bandgap fibres.

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Metastable Magnesium fluorescence spectroscopy using a frequency-stabilized 517 nm laser

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Phase-sensitive noise suppression in a photoacoustic sensor based on acoustic circular membrane modes

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Design and experimental verification of a photoacoustic flow sensor using computational fluid dynamics

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Portable optical frequency standard based on sealed gas-filled hollow-core fiber using a novel encapsulation technique

Mg I transitions for the stable isotopes