Conditional generation scheme for a high-purity superposed state of single and two-photon states by mixing two coherent beams with squeezed vacuum states
Sun-Hyun Youn · Journal of the Korean Physical Society · 2014
The numerical conditions to generate high-purity |1 >, |2 >, and |1 > + re iψ |2 > states were found from the explicit form of the probability amplitudes for two cascade-placed beam splitters with one squeezed state input and two coherent state inputs. The expected theoretical signal-tonoise ratio is more than 1000. Controlling the amplitudes and the phases of two coherent beams, as well as the transmittances of two beam splitters, allow various quantum states to be manipulated with a high signal-to-noise ratio. High-purity nonclassical states are expected to be a key element in quantum information science.