Science Daily January 22, 2021
An international team of researchers (Australia, France) combined phase stabilisation technology with advanced self-guiding optical terminals that allowed laser signals to be sent from one point to another without interference from the atmosphere. They demonstrated phase-stabilized optical frequency transfer over a 265 m horizontal point-to-point free-space link between optical terminals with active tip-tilt mirrors to suppress beam wander, in a compact, human-portable set-up. They could correct for atmospheric turbulence in 3D, that is, left-right, up-down and, critically, along the line of flight. According to the researchers if you have one of these optical terminals on the ground and another on a satellite in space, then you can start to explore fundamental physics, everything from testing Einstein’s theory of general relativity more precisely than ever before, to discovering if fundamental physical constants change over time. It could help increase the data rate from satellites to ground by orders of magnitude…read more. Open Access TECHNICAL ARTICLEÂ
Point-to-point phase-stabilized optical frequency transfer between buildings. Credit: Nature Communications volume 12, Article number: 515 (2021)