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abstract: 'We theoretically propose a method for on-demand generation of traveling Schrödinger cat states, namely, quantum superpositions of distinct coherent states of traveling fields. This method is based on deterministic generation of intracavity cat states using a Kerr-nonlinear parametric oscillator (KPO) via quantum adiabatic evolution. We show that the cat states generated inside a KPO can be released into an output mode by controlling the parametric pump amplitude dynamically. We further show that the quality of the traveling cat states can be improved by using a shortcut-to-adiabaticity technique.'
author:
- 'Hayato Goto,$^1$ Zhirong Lin,$^2$ Tsuyoshi Yamamoto,$^{2,3}$ and Yasunobu Nakamura$^{2,4}$'
title: 'On-Demand Generation of Traveling Cat States Using a Parametric Oscillator'
---

Introduction
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Quantum superposition is one of the most strange and intriguing concepts in quantum mechanics and a useful resource for quantum information processing. Superpositions of macroscopically distinct states are often referred to as Schrödinger cat states, or cat states for short, named after Schrödinger’s famous gedankenexperiment with a cat in a superposition of alive and dead states [@Haroche2013a; @Wineland2013a]. In quantum optics, superpositions of distinct coherent states are called cat states [@Leonhardt], because coherent states are often regarded as the “most classical" states of light.

Such cat 