Breaking the atmospheric barrier to send signals from Earth to spaceOne of the biggest hurdles in setting up a global quantum internet has been overcoming atmospheric turbulence. Until this week, the prevailing belief was that sending sensitive quantum signals from Earth to satellites was practically impossible or highly unstable, and that only the reverse path (from space to Earth) was feasible.
But researchers from the University of Technology Sydney (UTS) have changed this belief in recent days.

⚠️ The main challenge: the invisible wall of the Earth’s atmosphere acts like a cloudy and turbulent lens. When photons carrying quantum information are shot from Earth to space, collisions with air layers cause the following factors to occur:
– Strong signal dispersion
– Eliminating entanglement
– Loss of quality of information before reaching the satellite

For this reason, previous designs had to build very complex and expensive satellites that would generate the signal themselves and send it back to Earth.

🛠 Solution: Adaptive Optics
In this new achievement, advanced adaptive optics technology is used; A technology that was previously used in huge astronomical telescopes.

This system works as follows:
1. A guiding laser measures atmospheric turbulence in real time.
2. Deformation mirrors on the floor precisely reverse optical distortion.
3. The “corrected” quantum signal is sent into space and arrives intact at the satellite receiver.

💡 The key advantage of architecture
– Cost reduction
– Increase the strength of this change of direction

This change of direction (sending from Earth to space) has important strategic advantages:

🛰 Simplicity of satellites
Satellites no longer need to be flying quantum computers; They only have the role of receiver or mirror.

Ground processing power
Sophisticated laser production and quantum processing equipment remains on Earth;
Where there is no limit to weight, energy and repair.

💸 Significant reduction in costs
Lighter satellites = cheaper to launch = more affordable global network.

✅ The practical result of the research
This research shows that:
– QKD secure communication with low earth orbit (LEO) satellites is quite possible.
– It becomes possible to connect continents without the need for submarine optical fiber.
– Virtually impenetrable encryption will be provided for sensitive data.
– The network has higher stability in different weather conditions.

This development shows that the quantum internet no longer requires sci-fi space equipment.
By transferring complexity from space to Earth, mankind has taken a giant step towards the commercialization and generalization of secure quantum communications.

Link to the source