Boeing is attempting to create a critical building block for a quantum communications network.
Teleportation is the stuff of science fiction TV shows like “Star Trek,” but Boeing soon plans to demonstrate the concept in a very real, albeit smaller, way.
The aerospace company plans to launch its Q4S satellite in 2026 to demonstrate quantum entanglement swapping, a process in which two pairs of quanta—in this case, photons—become linked so that a change to one immediately affects the other no matter their distance apart. The “spooky action at a distance” phenomenon, as Albert Einstein called it, allows for quantum teleportation of information.
By demonstrating quantum entanglement and swapping in space, Boeing is attempting to create a critical building block for a quantum communications network that could link quantum computers and sensors, enabling a variety of previously thought impossible tasks including quantum telescopes that could capture and process information at the single-photon level.
“An array of telescopes around the Earth, connected with a quantum network, could go and image one of the rovers on Mars,” says Makan Mohageg, principal applied quantum physicist at Boeing. “It’s really wild.”
Boeing’s Q4S satellite is named after the four photons that it will attempt to entangle. To do that, its system will use a process called spontaneous parametric down-conversion in which a laser beam is passed through a nonlinear optical crystal to split one photon into a pair of entangled photons. After creating two pairs of photons, a photon from one pair is then entangled with a photon from another, thus swapping entanglement between the two sets.
In a future quantum communications network, if the two sets of photons (A & B and C & D) were paired at distant locations and then one of each pair (B and D) was sent via laser communications to a satellite, the entanglement of those photons at the satellite would also instantaneously entangle those left on Earth (A and C). A hypothetical quantum communications network would still require classical communications tools, such as a laser terminal or radio, to transmit the results of what is known as the Bell State Measurement to quantify the photons’ state.
Boeing has demonstrated quantum entanglement swapping on tabletop experiments at HRL Laboratories, a research facility in Malibu, California, that it operates jointly with General Motors Co. Its satellite demonstration will test how the harsh environment of space, including radiation, affects entanglement swapping. The company is also testing a quantum entanglement-swapping protocol to enable it to scale a future communications network.
Although Boeing builds a variety of satellites, it chose to host its quantum entanglement swapping payload on a small spacecraft developed by Astro Digital. That satellite can provide 70 watts to 80 watts of continuous power, which is critical for the project. The Q4S satellite will operate in a Sun-synchronous orbit, at about 550 km (341.7 mi.) in altitude.
Prior quantum satellite demonstrations done by China, for instance, have shown the ability to perform Quantum Key Distribution in space, a system in which single-photon states or entangled photon pairs are used to generate and distribute encryption keys securely. Boeing contends its quantum entanglement swapping experiment is more complex and has a greater potential impact.
In addition to quantum telescopes and boosting the capabilities of quantum computers, the company sees a quantum network as useful for “exceedingly precise time synchronization,” says Jay Lowell, chief engineer for Boeing’s Disruptive Computing, Networks & Sensors organization. “Entanglement collapses at a very small time overlap. We’re talking less than a couple hundred femtoseconds.” More precise timing could be used for positioning, navigation and timing technologies, for example.
Boeing is bullish on quantum communications and is spending internal R&D funds on the Q4S experiment, Lowell adds.
“We’ve put this as one of the cornerstones of our quantum portfolio strategy,” he says. “We’re making a big bet on quantum technology.”
Related Content
