ETH laser heading into the stratosphere with NASA

Astrophysicists will be flying into the stratosphere in a converted Boeing 747SP to measure infrared signals from cooling gases. They are hoping to gain new insights into how stars form in our galaxy. ETH physicist Lorenzo Bosco will also be aboard this unusual flight in a special aircraft of the National Aeronautics and Space Administration (NASA). Together with his team, he has developed a special laser that makes these measurements possible in the first place.

The ETH researchers developed a quantum cascade laser that can be used to visualise weak infrared signals from space. They are so weak that they can only be measured using a trick: the frequency of the incident light is changed using a local oscillator so that it can be better distinguished from the background noise. The principle behind this laser was first implemented in the 1990s and has now been specifically tailored to the astrophysicists’ requirements.

“The challenge was to develop a device that provides a precise and powerful signal with a clearly definable frequency,” explained ETH Professor Jérôme Faist in a press release. He hopes that the mission will also provide indications of how the laser might be further improved so that the astrophysicists can conduct infrared measurements with higher resolutions on their flights.