Recent research has demonstrated the feasibility of sending quantum signals from Earth to satellites, a development that could revolutionize quantum communication technologies. Professors Simon Devitt and Alexander Solntsev took the lead on this innovative study, which revealed some thrilling discoveries. According to their research, it’s now feasible to transmit quantum signals directly up to a satellite, a challenge once considered impossible.
The paper highlights a creative endeavor. Two individual particles of light, or photons, are fired from different ground stations towards a satellite flying roughly 500 kilometers above the Earth’s surface. To put this in greater context, this satellite is traveling at an incredible speed of 20,000 km/h. Photons are tailored to focus exactly on the satellite. This convergence allows them to feel quantum interference, a phenomenon crucial for efficient quantum communication.
Meanwhile, 2025 saw the Jinan-1 microsatellite reset the record high. It has notably validated a 12,900-kilometer quantum entanglement link between China and South Africa. Significantly, this satellite only demands a small optical apparatus to disrupt incoming photons and testify outcomes. This new approach cuts out the need for high-fidelity quantum hardware capable of generating trillions of entangled photons per second. As a result, it significantly reduces cost and complexity.
The uplink approach would be able to deliver such bandwidth,” Professor Devitt said.…This is because the satellite only requires a simple optical device to mask incoming photons and signal detection or non-detection as opposed to quantum technology to generate the trillions upon trillions of photons per second required to surpass losses to the ground.
During the mission, the two ground stations transmit their halves of the Bell pairs, entangled photon pairs, to the satellite. They accomplish this with an uplink channel that is built into the experimental setup. Existing quantum satellites produce entangled pairs in space. They then send each half down to two locations on earth, known as downlinks.
“Current quantum satellites create entangled pairs in space and then send each half of the pair down to two places on Earth—called a ‘downlink,’” said Professor Solntsev.
Professor Devitt emphasized the challenges overcome in this research, stating, “Surprisingly, our modeling showed that an uplink is feasible. We included real-world effects such as background light from the earth and sunlight reflections from the moon, atmospheric effects, and the imperfect alignment of optical systems.”
The meanings of this research go far beyond how to communicate. Though creating a quantum internet comes with its own set of obstacles, Professor Devitt noted. It requires orders of magnitude greater photons and bandwidth to reliably connect quantum computers than the use case for today’s cryptography.
In the future, quantum entanglement is going to be more akin to electricity, he stated. More like a commodity that we rarely talk about that powers everyone’s cars. It is created and delivered in ways that we don’t always understand. We don’t think about it, we just plug our appliances in and use them.
This study was published with DOI: 10.1103/v3p1-kz4h, and Phys.org reported on these findings on November 5, 2025. The ongoing exploration of quantum communication methods holds promise for advancing technologies that rely on secure and efficient data transmission.
