This paper introduces quantum microscopy by coincidence (QMC) with balanced pathlengths, achieving super-resolution imaging at the Heisenberg limit. QMC utilizes entangled photons, where the balanced pathlengths in a symmetric configuration allow the photon pair to behave like a single photon with half the wavelength, doubling the resolution. The method demonstrates significantly improved speed and contrast-to-noise ratio (CNR) compared to existing wide-field quantum imaging techniques, along with substantially increased resistance to stray light. Experiments on cancer cells demonstrate a resolution of 1.4 µm, showcasing the potential for non-destructive bioimaging.

Zhe He, Yide Zhang, Xin Tong, Lei Li, Lihong V. Wang