Entangling Schrödinger's cat states by bridging discrete- and continuous-variable encoding
Artikel i vetenskaplig tidskrift, 2025

In quantum information processing, two primary research directions have emerged: one based on discrete variables (DV) and the other on the structure of quantum states in a continuous-variable (CV) space. Integrating these two approaches could unlock new potentials, overcoming their respective limitations. Here, we show that such a DV-CV hybrid approach, applied to superconducting Kerr parametric oscillators (KPOs), enables us to entangle a pair of Schr & ouml;dinger's cat states by two methods. The first involves the entanglement-preserving conversion between Bell states in the Fock-state basis (DV encoding) and those in the cat-state basis (CV encoding). The second method implements a iSWAP\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sqrt{{{{\rm{iSWAP}}}}}$$\end{document} gate between two cat states following the procedure for Fock-state encoding. This simple and fast gate operation completes a universal quantum gate set in a KPO system. Our work offers powerful applications of DV-CV hybridization and marks a first step toward developing a multi-qubit platform based on planar KPO systems.

Författare

Daisuke Hoshi

RIKEN Center for Computational Science

Tokyo University of Science

Toshiaki Nagase

RIKEN Center for Computational Science

Tokyo University of Science

Sangil Kwon

Tokyo University of Science

Daisuke Iyama

Tokyo University of Science

RIKEN Center for Computational Science

Takahiko Kamiya

Tokyo University of Science

RIKEN Center for Computational Science

Shiori Fujii

RIKEN Center for Computational Science

Tokyo University of Science

Hiroto Mukai

RIKEN Center for Computational Science

Tokyo University of Science

Shahnawaz Ahmed

Chalmers, Mikroteknologi och nanovetenskap, Tillämpad kvantfysik

Anton Frisk Kockum

Chalmers, Mikroteknologi och nanovetenskap, Tillämpad kvantfysik

Shohei Watabe

Tokyo University of Science

Shibaura Institute of Technology

Fumiki Yoshihara

Tokyo University of Science

Jaw-Shen Tsai

Tokyo University of Science

RIKEN Center for Computational Science

Nature Communications

2041-1723 (ISSN) 20411723 (eISSN)

Vol. 16 1 1309

Stora atomer - en ny regim för kvantoptik

Vetenskapsrådet (VR) (2019-03696), 2020-01-01 -- 2023-12-31.

Kvantsimulering och kvantkommunikation med stora atomer

Stiftelsen för Strategisk forskning (SSF) (FFL21-0279), 2022-08-01 -- 2027-12-31.

Open Superconducting Quantum Computers (OpenSuperQPlus)

Europeiska kommissionen (EU) (EC/HE/101113946), 2023-03-01 -- 2026-08-31.

Ämneskategorier (SSIF 2025)

Subatomär fysik

DOI

10.1038/s41467-025-56503-8

PubMed

39900944

Mer information

Senast uppdaterat

2025-11-04