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arXiv · 2501.14104

Quantum enhanced beam tracking surpassing the Heisenberg uncertainty limit

Yingwen Zhang·Duncan England·Noah Lupu-Gladstein·Frederic Bouchard·Guillaume Thekkadath·Philip J. Bustard·Ebrahim Karimi·Benjamin Sussman
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Abstract

Determining a beam's full trajectory requires tracking both its position and momentum (angular) information. However, the product of position and momentum uncertainty in a simultaneous measurement of the two parameters is bound by the Heisenberg uncertainty limit (HUL). In this work, we present a proof-of-principle demonstration of a quantum-enhanced beam tracking technique, leveraging the inherent position and momentum entanglement between photons produced via spontaneous parametric down-conversion (SPDC). We show that quantum entanglement can be exploited to achieve a beam tracking accuracy beyond the HUL in a simultaneous measurement. Moreover, with existing detection technologies, it is already possible to achieve near real-time beam tracking capabilities at the single-photon level. The technique also exhibits high resilience to background influences, with negligible reduction in tracking accuracy even when subjected to a disruptive beam that is significantly brighter than SPDC.

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Yingwen Zhang, Duncan England, Noah Lupu-Gladstein, Frederic Bouchard, Guillaume Thekkadath, Philip J. Bustard, Ebrahim Karimi, Benjamin Sussman. 2025-01-23. Quantum enhanced beam tracking surpassing the Heisenberg uncertainty limit. https://doi.org/10.1103/physrevlett.134.190804

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