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Related papers: Measuring the size of a Schroedinger cat state

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Flux qubits, small superconducting loops interrupted by Josephson junctions, are successful realizations of quantum coherence for macroscopic variables. Superconductivity in these loops is carried by $\sim 10^6$ -- $10^{10}$ electrons,…

Quantum Physics · Physics 2015-05-14 J. I. Korsbakken , F. K. Wilhelm , K. B. Whaley

A misunderstanding of entangled states has spawned decades of concern about quantum measurements and a plethora of quantum interpretations. The "measurement state" or "Schrodinger's cat state" of a superposed quantum system and its detector…

Quantum Physics · Physics 2019-10-28 Art Hobson

An interferometric experiment is described that characterizes an optical cat state in a cavity mode. Our method describes how to measure the amplitude and phase of the different coherent states that make up the cat states. We show that…

Quantum Physics · Physics 2017-06-30 Marvellous Onuma-Kalu , Kae Nemoto , W. J. Munro , Robert B. Mann

Macroscopic quantum superpositions, such as mechanical Schr\"odinger cat states, are central to emerging quantum technologies in sensing and bosonic error-correcting codes. We propose a scheme to generate such states by coupling a…

Quantum Physics · Physics 2026-01-26 M. Tahir Naseem

In the Schr\"odinger-cat gedanken experiment a cat is in a quantum superposition of two macroscopically distinct states, alive and dead.The paradoxical interpretation of quantum mechanics is that the cat is not in one state or the other,…

Quantum Physics · Physics 2007-05-23 M. D. Reid

In this paper, we consider the preparation of Schr\"odinger cat states using a measurement-assisted gate based on the Fock resource state, the quantum non-demolition (QND) entangling operation, and the homodyne measurement. Previously we…

Quantum Physics · Physics 2024-01-02 A. V. Baeva , N. G. Veselkova , N. I. Masalaeva , I. V. Sokolov

The ability of matter to be superposed at two different locations while being intrinsically connected by a quantum phase is among the most counterintuitive predictions of quantum physics. While such superpositions have been created for a…

Quantum Physics · Physics 2016-04-13 D. Kienzler , C. Flühmann , V. Negnevitsky , H. -Y. Lo , M. Marinelli , D. Nadlinger , J. P. Home

We propose a detection scheme for measuring the overlap of the quantum state of a weakly excited traveling-field mode with a desired reference quantum state, by successive mixing the signal mode with modes prepared in coherent states and…

Quantum Physics · Physics 2016-05-10 J. Clausen , M. Dakna , L. Knoll , D. -G. Welsch

We discuss the possibility of generating and detecting, by a tomographic reconstruction of the Wigner function, a macroscopic superposition of two coherent states. The superposition state is created using a conditioned measurement on the…

Quantum Physics · Physics 2009-11-06 M. Genovese , C. Novero

In quantum optics, photonic Schr\"odinger cats are superpositions of two coherent states with opposite phases and with a significant number of photons. Recently, these states have been observed in the transient dynamics of…

Quantum Physics · Physics 2016-06-03 F. Minganti , N. Bartolo , J. Lolli , W. Casteels , C. Ciuti

We suggest a scheme to generate a macroscopic superposition state (Schrodinger cat state) of a free-propagating optical field using a beam splitter, homodyne measurement and a very small Kerr nonlinear effect. Our scheme makes it possible…

Quantum Physics · Physics 2009-11-10 H. Jeong , M. S. Kim , T. C. Ralph , B. S. Ham

We consider the generation of Schr{\"o}dinger cat states using a quantum measurement-induced logical gate where entanglement between the input state of the target oscillator and the Fock state of the ancillary system produced by the quantum…

Quantum Physics · Physics 2025-07-16 N. G. Veselkova , Roman Goncharov , Alexei D. Kiselev

Entanglement is the quintessential quantum phenomenon and a key enabler of quantum algorithms. The ability to faithfully entangle many distinct particles is often used as a benchmark for the quality of hardware and control in a quantum…

Quantum Physics · Physics 2025-10-13 Ali Javadi-Abhari , Simon Martiel , Alireza Seif , Maika Takita , Ken X. Wei

We present what is to our knowledge the first implementation of a Schr\"odinger cat states "breeding" operation, which allows an iterative growth of these states. We thus report the experimental generation of a squeezed Schr\"odinger cat…

Quantum Physics · Physics 2014-12-11 Jean Etesse , Martin Bouillard , Bhaskar Kanseri , Rosa Tualle-Brouri

We proposed and analyzed a scheme to generate large-size Schr\"{o}dinger cat states based on linear operations of Fock states and squeezed vacuum states and conditional measurements. By conducting conditional measurements via photon number…

Quantum Physics · Physics 2022-05-04 Hongbin Song , Guofeng Zhang , Xiaoqiang Wang , Hidehiro Yonezawa , Kaiquan Fan

Parallel worlds are imaginative ideas in quantum mechanics and cosmology. The superpositions of parallel worlds are novel states of quantum gravity and have no classical correspondences generally. In this letter, we investigate the…

Quantum Physics · Physics 2021-11-02 Yu-Qing Cui , Tian-Ming Zhao , Rong-Xin Miao , Jin-Dong Wang , Huanyang Chen

Superposed coherent states are central to quantum technologies, yet their reliable identification remains a challenge, especially in noisy or resource-constrained settings. We introduce a novel, directly measurable criterion for detecting…

Quantum Physics · Physics 2026-04-27 Šimon Bräuer , Jan Provazník , Vojtěch Kala , Petr Marek

Although quantum mechanics is a mature theory, fundamental problems discussed during its time of foundation have remained with us to this day. These problems are centered on the problematic relation between the quantum and classical worlds.…

Quantum Physics · Physics 2007-05-23 G. B. Lesovik , A. V. Lebedev , G. Blatter

Recent development in quantum information sciences and technologies, especially building programmable quantum computers, provide us new opportunities to study fundamental aspects of quantum mechanics. We propose qubit models to emulate the…

Quantum Physics · Physics 2022-06-29 Meng-Jun Hu , Yanbei Chen , Yiqiu Ma , Xiang Li , Yubao Liu , Yong-Sheng Zhang , Haixing Miao

We investigate the feasibility of observing matter-wave interference of a micron-sized charged particle by putting it into a quantum superposition of states with a distinguishable separation. In the proposed method, an atomic ion is…

Quantum Physics · Physics 2022-04-06 Sebastian Leontica , Christopher Foot