High-sensitivity imaging with quantum spatial correlation of twin beams

The first part of our work is devoted to identify regimes suitable for weak image detection. Moreover, we investigate a method of data analysis that identifies the centre of symmetry of the signal-idler images with a sub-pixel precision. In the second part of our work we study an imaging scheme, where a weakly absorbing object is posed in the far-field of the signal beam and the image is retrieved by subtracting pixel by pixel the signal idler intensities. We show that imaging with spatially correlated twin beams provides a substantial enhancement of the signal-to-noise ratio with respect to classical imaging in a domain of parameters accessible to experimental implementations.