Fig. 1: Schematic illustration for achieving quantum squeezing amplification with a Kerr nonlinear oscillator.
From: Quantum squeezing amplification with a weak Kerr nonlinear oscillator
a Energy level diagram of a linear harmonic oscillator (gray dashed lines) and a Kerr nonlinear oscillator (solid blue lines) with an engineered detuned drive of frequency ωd and amplitude Ωd (green wavy line). b The quantum evolution of a coherent state represented with Wigner functions in phase space, exhibiting squeezing and collapse without any drives on the Kerr oscillator. c The quantum evolution of a coherent state to realize cyclic squeezing amplification with an engineered detuned drive on the Kerr oscillator. The coherent state undergoes a cyclic evolution in the phase space and becomes a squeezed state at the final moment of each cycle, where the squeezing degree gradually increases with the number of cycles. d The quantum evolution in phase space with the Trotterization technique using displacement operations (yellow arrows) and Kerr-nonlinear rotations (blue arrows), showing the transition from a coherent state to a squeezed state.
