tunable lasers

An image in Claude Cohen-Tannoudji's 1994 paper, commemorating the contributions of S. Pancharatnam. Credit: Current Science

Catching a Glimpse of S. Pancharatnam in History’s Precisest Chemical Reaction

The new PARLA laser in operation at ESO’s Paranal Observatory. The yellow-orange beam of the brilliant seven-watt laser is seen emerging from the dome of Unit Telescope 4 of the Very Large Telescope. In the background the Large Magellanic Cloud can also be seen. The laser creates an artificial star high in the atmosphere that can be used to correct images for the turbulence of the air and form much sharper pictures. Credit: European Southern Observatory, CC BY 4.0

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