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
Tokyo University of Science
RIKEN
Toshiaki Nagase
RIKEN
Tokyo University of Science
Sangil Kwon
Tokyo University of Science
Daisuke Iyama
RIKEN
Tokyo University of Science
Takahiko Kamiya
RIKEN
Tokyo University of Science
Shiori Fujii
Tokyo University of Science
RIKEN
Hiroto Mukai
RIKEN
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
RIKEN
Tokyo University of Science
Nature Communications
2041-1723 (ISSN) 20411723 (eISSN)
Vol. 16 1 1309Kvantsimulering 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.
Stora atomer - en ny regim för kvantoptik
Vetenskapsrådet (VR) (2019-03696), 2020-01-01 -- 2023-12-31.
Ämneskategorier (SSIF 2025)
Subatomär fysik
DOI
10.1038/s41467-025-56503-8
PubMed
39900944