Inherently unpredictable beam steering for quantum LiDAR
Abstract
Quantum LiDAR offers noise resilience and stealth observation capabilities in low-light conditions. In prior demonstrations, the telescope pointing was raster-scanned, making the observation direction predictable from the pointing direction. However, while Quantum LiDAR can enable stealth observation, operational stealth is enhanced by inherently unpredictable beam steering. Here, we introduce a novel stealth beam steering method that is fundamentally immune to prediction. In a photon pair, the probe photon undergoes diffraction in an unpredictable direction at a grating due to wavelength randomness. The arrival time of the heralding photon, delayed by propagation through a dispersive medium, enables the determination of the probe photon's diffraction direction. Our method successfully detects multiple targets in parallel, demonstrating up to a 1000-fold enhancement in signal-to-noise ratio compared to classical LiDAR. This breakthrough establishes a new paradigm for quantum-enhanced sensing, with far-reaching implications for quantum metrology, secure communications, and beyond.
Cite
@article{arxiv.2511.09089,
title = {Inherently unpredictable beam steering for quantum LiDAR},
author = {Junyeop Kim and Dongjin Lee and Woncheol Shin and Yeoulheon Seong and Heedeuk Shin},
journal= {arXiv preprint arXiv:2511.09089},
year = {2025}
}
Comments
Main text (11 pages and 5 figures), Supplementary information (9 pages and 7 figures)