image: ©imaginima | iStock
University of Michigan engineers are leading a $9 million initiative to develop entangled quantum sensor networks. By linking sensors through quantum states, the team aims to revolutionise navigation and timing with record-breaking sensitivity
A University of Michigan-led team has secured $9 million from the U.S. Office of Naval Research to explore the fundamental limits of quantum networking. The five-year project aims to develop sensor networks linked through quantum entanglement—a phenomenon where particles remain connected regardless of the distance between them.
By harnessing these quantum links, the team intends to create sensing systems with unprecedented levels of precision and speed.
Breaking traditional sensitivity limits
In a conventional sensor network, measurement sensitivity typically improves at a rate relative to the square root of the number of sensors. However, by using entangled states, the researchers believe they can achieve a “quantum leap” in performance, where sensitivity improves with the square of the number of sensors.
“Entanglement can allow you to improve the performance of a sensor network in terms of resolution,” says project leader Zheshen Zhang. This means these networks could detect finer details and process signals with a much higher signal-to-noise ratio than current technology allows. Potential applications include ultra-precise atomic clocks, magnetic field sensing, and autonomous navigation systems that do not rely on GPS.
Proving the theory with dual testbeds
To validate their methods, the multidisciplinary team will utilise two distinct quantum testbeds:
Rydberg atom arrays:
These involve atoms with “roving” electrons that are highly sensitive to electric and magnetic fields. By using lasers to place these atoms into a state of quantum superposition, the team can create an array of several hundred qubits that react instantly to signals as a single, unified sensor.
Mechanical membranes:
This testbed uses thin membranes that vibrate in response to light, much like a human eardrum responds to sound. Researchers will cool these sensors to 0.1 Kelvin—nearly absolute zero—and link them using entangled light to suppress thermal noise.
Laying the groundwork for a quantum internet
A significant challenge for the team is maintaining entanglement over time. Environmental “noise” can easily break the delicate bonds between entangled atoms, destroying the quantum advantage. The project will focus on developing error suppression and correction techniques to keep these networks stable.
The findings from this initiative are expected to provide the foundational building blocks for a future quantum internet, where distributed sensors and computers work together across vast distances with perfect synchronisation.