Multimode Qubit-Conditional Operations via Generalized Cross-Resonance

Abstract: We present a general framework for generating single- and multimode qubit-conditional operations by extending cross-resonant driving to a generalized multimode scheme. This includes single-mode conditional displacements and squeezing induced by one- and two-photon cross-resonant drives in the presence of one- and two-photon qubit-oscillator interactions, respectively. In the multimode setting, we derive multimode qubit-conditional beamsplitter and two-mode squeezing operations. We highlight their significance for bosonic quantum computing and quantum simulations. We also discuss possible implementations with superconducting circuits.