Multimode diode laser correlation spectroscopy using gas-filled porous materials for pathlength enhancement

• A novel pathlength enhancement approach has been applied in multimode diode laser correlation spectroscopy measurements of gas concentrations. Reference and sample gas cells made of porous polystyrene foam and alumina ceramic, respectively, were employed in proof-of-principle measurements of molecular oxygen. Equivalent pathlengths of 164 and 52 cm were obtained for the reference and sample cells with physical pathlengths of 4 and 1 cm, respectively. With a measurement time of 60 s, a physical-pathlength-integrated sensitivity of 15 ppma <...m was achieved with an enhancement of more than one order of magnitude compared with an open-air setup. Practical application aspects were investigated including gas cell size and light alignment tolerance. This generic approach for pathlength enhancement provides advantages in terms of compactness and robustness.

Ämnesord

NATURVETENSKAP  -- Fysik -- Atom- och molekylfysik och optik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Atom and Molecular Physics and Optics (hsv//eng)

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)