Space probes and orbital telescopes operate outside the Sun’s “energy umbrella,” so every watt of power on board is worth its weight in gold. A new study by the TU Wien team offers a solution: autonomous quantum clocks whose accuracy increases exponentially, while heat loss increases only logarithmically. In other words, for the same amount of energy, it is possible to achieve stability that is thousands of times better than current principles allow.
How the “two-stage” mechanism works
Coherent circuit: a quantum particle rotates without loss along a ring — this is a fast and thermodynamically silent mode.
Dissipative node: only when a particle passes through a single control point, the system records the “current” and releases a minimum amount of entropy.
The combination results in clocks in which each additional bit of loss brings arithmetically more accuracy than in conventional atomic or optical standards.
The illustration shows the idea of a “two-stage” quantum clock:
- (a) — a “multi-ring” consisting of dozens of “cup” resonators. One quantum particle moves in a circle; when it completes a full rotation, the clock “ticks.” Fire and ice represent warm and cold contacts, which determine the direction of movement.
- (b) — a simplified energy diagram of one of the “cups,” which shows how the thermal gradient causes the particle to jump forward rather than backward.
- (c) — graph: the blue step shows how the tick counter grows almost uniformly over time; the gray corridor represents a small statistical error.
- (d) — another graph, where the blue dots represent the strength of the connection between neighboring “cups,” which first grows smoothly, then becomes equal, and finally changes slightly again so that the wave does not reflect back.
Why is this critical for astronomy?
For missions on the outskirts of the Solar System or in orbit, accurate time is essential for synchronizing laser rangefinders, interferometry, and gravimetric experiments. The transition from watts to microwatts allows:
- placing clocks in small CubeSat groups for long-term VLBI observations;
- reducing the weight and heat dissipation on board heliophysical instruments;
- increasing the sensitivity of gravitational wave detectors — less noise, higher Q-factor of optical cavities.
Highly accurate but “cold” chronometers are needed wherever energy resources are limited: in quantum networks, autonomous sensors, medical implants, and portable navigation systems. Potentially, this technology could even become part of the new international standard for the second, which is currently being prepared for approval in the 2030s. Thus, quantum clocks could become a basic module for navigation and scientific experiments in deep space, where energy and time stability are key to mission success.
When will this and other technologies be implemented in real space missions? Read about it in our article “Space missions 2025: the most important things a human will do in space this year.”
