Enhancing the super-resolution of incoherent sources via noiseless attenuation

Imaging of two incoherent point sources provides basic building block for the fluorescence microscopy and astronomical observation. Here, we demonstrate that the measurement sensitivity per detected photon (SPDP) can be enhanced by adding a noiseless attenuation operation in a traditional imaging system, where the noiseless attenuator can be simulated by a beam splitter assisted by vacuum detection. The results show that the noiseless attenuation operation can outperform the normal attenuation operation in terms of SPDP. This advantage can be attributed to the noiseless attenuation technology that attenuates signal without introducing additional classical and quantum noise. Moreover, even when considering practical imperfections, such as misalignment of the demultiplexer base relative to the centroid of the two sources, the noiseless attenuation imaging system can still maintain its advantage. Our results have potential applications in quantum super-resolution imaging and quantum metrology.