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Related papers: Measuring the size of a Schroedinger cat state

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The manuscript investigates the entropy squeezing of a qubit (two-level atom) interacting with the cavity field in the Schr\"odinger cat states. The effects of the Schr\"odinger cat states of the field on the squeezing are examined. Our…

Quantum Physics · Physics 2017-10-25 Wei-Guang Wang , Xue-Qun Yan , Jiu-Ming LI

We propose a scheme to create a macroscopic ``Sch\"odinger cat'' state formed by two interacting Bose condensates. In analogy with quantum optics, where the control and engineering of quantum states can be maintained to a large extend, we…

Quantum Physics · Physics 2009-10-30 J. I. Cirac , M. Lewenstein , K. Moelmer , P. Zoller

We propose an optical scheme to generate a superposition of coherent states with enhanced size adopting an interferometric setting at the single-photon level currently available in the laboratory. Our scheme employs a nondegenerate optical…

Quantum Physics · Physics 2012-06-19 Chang-Woo Lee , Jinhyoung Lee , Hyunchul Nha , Hyunseok Jeong

Quantum superpositions of macroscopically distinct classical states, so-called Schr\"{o}dinger cat states, are a resource for quantum metrology, quantum communication, and quantum computation. In particular, the superpositions of two…

We consider fundamental limits on the detectable size of macroscopic quantum superpositions. We argue that a full quantum mechanical treatment of system plus measurement device is required, and that a (classical) reference frame for phase…

Quantum Physics · Physics 2017-11-27 M. Skotiniotis , W. Dür , P. Sekatski

We show how macroscopically distinct quantum superposition states (Schroedinger cat states) may be used as logical qubit encodings for the correction of spontaneous emission errors. Spontaneous emission causes a bit flip error which is…

Quantum Physics · Physics 2009-10-31 P. T. Cochrane , G. J. Milburn , W. J. Munro

In this paper we re-investigate the core of Schroedinger's 'cat paradox'. We argue that one has to distinguish clearly between superpositions of macroscopic cat states and superpositions of entangled states which comprise both the state of…

Quantum Physics · Physics 2009-11-13 S. Rinner , E. Werner

"Schrodinger's cat" is a gedankenexperiment intended to highlight conceptual difficulties in the interpretation of quantum mechanics. The generation of 'cat-like' states is central to numerous quantum information protocols. In particular,…

Quantum Physics · Physics 2010-06-15 Itai Afek , Oron Ambar , Yaron Silberberg

Pure states are usually used to observe quantum phenomena. In this study, we show that a quantum superposition of spatially displaced mixed cat states can be generated within an optical waveguide via nonparaxial unitary evolution of the…

Quantum Physics · Physics 2025-12-01 N. I. Petrov

In Rydberg dressed ultra-cold gases, ground state atoms inherit properties of a weakly admixed Rydberg state, such as sensitivity to long-range interactions. We show that through hyperfine-state dependent interactions, a pair of atom clouds…

Atomic Physics · Physics 2012-12-19 S. Möbius , M. Genkin , A. Eisfeld , S. Wüster , J. -M. Rost

We investigate the possibility of interference effects induced by macroscopic quantum-mechanical superpositions of almost othogonal coherent states - a Schroedinger cats state - in a resonant microcavity. Despite the fact that a single…

Quantum Physics · Physics 2009-11-06 Bo-Sture K Skagerstam , Bjorn A Bergsjordet , Per K. Rekdal

In this study, we have proposed a method based on non-equilibrium effects to generate the superposition of macroscopically distinguishable quantum states, known as Schrodinger cat states, by using a Mach-Zehnder interferometry type…

Quantum Physics · Physics 2020-06-24 Arash Tirandaz , Hamid Reza Naeij , Afshin Shafiee

We report on deterministic generation of 18-qubit genuinely entangled Greenberger-Horne-Zeilinger (GHZ) state and multi-component atomic Schr\"{o}dinger cat states of up to 20 qubits on a quantum processor, which features 20 superconducting…

Using different optical setups based on squeezed state and photon subtraction we show how optical entanglement between a macroscopic and a microscopic state - the so-called Schrodinger cat state or micro-macro state - can be generated. The…

Quantum Physics · Physics 2013-11-13 Ulrik L. Andersen , Jonas S. Neergaard-Nielsen

Quantum entanglement involving coherent superpositions of macroscopically distinct states is among the most striking features of quantum theory, but its realization is challenging, since such states are extremely fragile. Using a…

We study quantum states produced by optimal phase covariant quantum cloners. We argue that cloned quantum superpositions are not macroscopic superpositions in the spirit of Schr\"odinger's cat, despite their large particle number. This is…

Quantum Physics · Physics 2012-10-26 F. Fröwis , W. Dür

We show that it is possible to measure Schrodinger wave of a single quantum system. This provides a strong argument for associating physical reality with the quantum state of a single system, and challenges the usual assumption that the…

High Energy Physics - Theory · Physics 2009-10-22 Yakir Aharonov , Lev Vaidman

High-dimensional quantum systems are a valuable resource for quantum information processing. They can be used to encode error-correctable logical qubits, which has been demonstrated using continuous-variable states in microwave cavities or…

A reason is discussed (may be not the only one) for why we do not see any superposition of macroscopic states in the real world. Under the general assumption that quantum macrostates are statistical ensembles of microstates, it is shown…

Quantum Physics · Physics 2026-05-18 Fabio Siringo

A measurement-induced continuous-variable logical gate is able to prepare Schr\"odinger cat states if the gate uses a non-Gaussian resource state, such as cubic phase state [I. V. Sokolov, Phys. Lett. A 384, 126762 (2020)]. Our scheme…

Quantum Physics · Physics 2021-12-08 N. I. Masalaeva , I. V. Sokolov