Compound beams for direct experimental comparison of quantum operations
The study uses compound beams, built from simple blocks forming quantum-correlated structures, to simulate quantum operations for creating nonclassical and entangled multi-mode states. It compares photon addition and subtraction in thermal, sub-Poissonian, and twin beams across two orders of magnitude in intensity. The findings show that addition enhances nonclassicality for thermal/sub-Poissonian states but subtraction is better for twin beams, allowing researchers to study quantum operations side-by-side.