Scientists have developed a new laser sensing technology that could allow soldiers to detect hidden bombs from a distance.The Princeton University technology may also help scientists better measure airborne environmental pollutants and greenhouse gasses.
"We are able to send a laser pulse out and get another pulse back from the air itself. The returning beam interacts with the molecules in the air and carries their finger prints," said Richard Miles, the research group leader and co-author on the paper.
Miles collaborated with three other researchers: Arthur Dogariu, the lead author on the paper, and James Michael of Princeton, and Marlan Scully, a professor with joint appointments at Princeton and Texas A&M University.
The new laser sensing method uses an ultraviolet laser pulse that is focused on a tiny patch of air, similar to the way a magnifying glass focuses sunlight into a hot spot.
Within this hot spot oxygen atoms become "excited" as their electrons get pumped up to high energy levels. When the pulse ends, the electrons fall back down and emit infrared light.
