Mode-Selective Photon Subtraction via Time-to-Frequency Mapping for Multimode Entangled States

Photonics quantum networks are pivotal for quantum technologies, facilitating efficient information distribution and manipulation through quantum states of light. Continuous-variable (CV) cluster states, essential resources for Measurement-Based Quantum Computing, can be deterministically generated using squeezed states of light and mode-basis changes [1]. However, Gaussian states like squeezed states or cluster states, can be efficiently simulated with a classical computer [2]. Thus, to achieve quantum advantage, non-Gaussianity should be introduced, which can be accomplished by subtracting a photon from a squeezed state [3].