Generation of an entangled cat state from a Bell state in two interacting Kerr Parametric Oscillators*

Kerr Parametric Oscillators (KPOs) are parametrically driven weakly nonlinear oscillators. These are promising quantum systems for generation and control of cat states, which can be useful for various applications, such as quantum error correction.

However, scaling with cat states is a non-trivial task because of complexity in entangled state generation compared to that in two-level system encoding.

In this talk, we present our recent experimental progress on a relatively simple method on generation of an entangled cat state from a Bell state in planar KPOs.

We first generate a Bell state by applying a parametric drive to one of KPOs. Subsequently, we create an entangled cat state by applying an adiabatic two-photon pump to each KPO. To characterize the generated entangled cat state, we perform two-mode Wigner tomography via joint measurement of ancilla transmons coupled to each KPO.  

The simplicity of our scheme and planar geometry will be beneficial for scaling.