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Related papers: Measuring the size of a Schroedinger cat state

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We investigate the quantum properties of superpositions of oppositely squeezed states, which can be regarded as Schrodinger cat states. Compared with conventional coherent-state cat states, these states exhibit distinct photon-number…

Quantum Physics · Physics 2025-11-06 Hiroo Azuma , William J. Munro , Kae Nemoto

We outline a toolbox comprised of passive optical elements, single photon detection and superpositions of coherent states (Schrodinger cat states). Such a toolbox is a powerful collection of primitives for quantum information processing…

Quantum Physics · Physics 2009-11-10 A. Gilchrist , Kae Nemoto , W. J. Munro , T. C. Ralph , S. Glancy , Samuel. L. Braunstein , G. J. Milburn

A scheme for generating Schr\"{o}dinger cat-like states of a single-mode optical field by means of conditional measurement is proposed. Feeding into a beam splitter a squeezed vacuum and counting the photons in one of the output channels,…

Quantum Physics · Physics 2009-10-30 M. Dakna , T. Anhut , T. Opartny , L. Knoll , D. -G. Welsch

The Schr\"odinger cat state plays a crucial role in quantum theory, and has important fundamental as well as technological implications, ranging from quantum measurement theory to quantum computers. The power of the potential implications…

Quantum Physics · Physics 2013-07-12 Utkarsh Mishra , Aditi Sen De , Ujjwal Sen

We give some arguments to evaluate the "size" of Schrodinger cat for the flux qubit, which has really different results from ref.[1] Korsbakken et al. [1] J.Korsbakken,F.K.Wilhelm and K.B.Whaley,Physics Scripta T137,014022 (2009)

Quantum Physics · Physics 2016-03-15 Anthony J. Leggett

Optical Schrodinger's cat (SC) is highly anticipated because of the potential of realizing fault-tolerant quantum computing, but the practical merit is only shown when the amplitude is larger than 2. However, such high-amplitude cats have…

Quantum Physics · Physics 2024-07-04 Nuo Wang , Xinchen Zhang , Qi Liu , Fengxiao Sun , Qiongyi He , Ying Gu

The entangled state that results when a detector measures a superposed quantum system has spawned decades of concern about the problem of definite outcomes or "Schrodinger's cat." This state seems to describe a detector in an indefinite or…

Quantum Physics · Physics 2022-06-14 Art Hobson

Schr\"{o}dinger cat states, consisting of superpositions of macroscopically distinct states, provide key resources for a large number of emerging quantum technologies in quantum information processing. Here we propose how to generate and…

Quantum Physics · Physics 2022-06-14 Baijun Li , Wei Qin , Ya-Feng Jiao , Cui-Lu Zhai , Xun-Wei Xu , Le-Man Kuang , Hui Jing

Quantum metrology with nonclassical states offers a promising route to improved precision in physical measurements. The quantum effects of Schr{\"o}dinger-cat superpositions or entanglements allow measurement uncertainties to reach below…

Quantum Physics · Physics 2025-07-11 Y. A. Yang , W. -T. Luo , J. -L. Zhang , S. -Z. Wang , Chang-Ling Zou , T. Xia , Z. -T. Lu

Linear superpositions of macroscopically distinct quantum states (sometimes also called Schr\"odinger cat states) are usually almost immediately reduced to a statistical mixture if exposed to the dephasing influence of a dissipative…

Quantum Physics · Physics 2007-05-23 Daniel Braun , Petr A. Braun , Fritz Haake

Contractive states for a free quantum particle were introduced by Yuen [Yuen H P 1983 Phys. Rev. Lett. 51, 719] in an attempt to evade the standard quantum limit for repeated position measurements. We show how appropriate families of two-…

Quantum Physics · Physics 2009-11-10 Lorenza Viola , Roberto Onofrio

Schr\"odinger's famous Gedankenexperiment has inspired multiple generations of physicists to think about apparent paradoxes that arise when the logic of quantum physics is applied to macroscopic objects. The development of quantum…

Quantum Physics · Physics 2021-03-22 Demid V. Sychev , Valeriy A. Novikov , Khurram K. Pirov , Christoph Simon , A. I. Lvovsky

Modeling the Schr\"{o}dinger cat by a two state system and assuming that the cat is coupled to the environment we look for the least paradoxical states of the Schr\"{o}dinger cat in the following way. We require the reduced density matrix…

Quantum Physics · Physics 2007-05-23 Andrey Pereverzev

Recently, using conditioning approaches on the high-harmonic generation process induced by intense laser-atom interactions, we have developed a new method for the generation of optical Schr\"odinger cat states (M. Lewenstein et al.,…

Schr\"odinger cat states are useful for many applications, ranging from quantum information processing to high-precision measurements. In this paper we propose a conceptually new method for creating such cat states, based on photon-assisted…

Mesoscale and Nanoscale Physics · Physics 2020-10-30 Jonas Lidal , Jeroen Danon

We consider a weakly interacting coherently coupled Bose-Einstein condensate in a double-well potential. We show by means of stochastic simulations that the system could possibly be driven to an entangled macroscopic superposition state or…

Statistical Mechanics · Physics 2022-09-21 J. Ruostekoski

The recent experiment on superconducting quantum interference device provides new opportunity to clarify the fundamental interpretation of quantum mechanics. After analyzing this and relevant experiments, we claim the point of view that the…

Quantum Physics · Physics 2016-09-08 Guang-jiong Ni

Optical "Schr\"odinger cat" states, the non-classical superposition of two quasi-classical coherent states, serve as a basis for gedanken experiments testing quantum physics on mesoscopic scales and are increasingly recognized as a resource…

The observation of quantum phenomena often necessitates sufficiently pure states, a requirement that can be challenging to achieve. In this study, our goal is to prepare a non-classical state originating from a mixed state, utilizing…

Quantum Physics · Physics 2025-04-08 Ian Yang , Thomas Agrenius , Vasilisa Usova , Oriol Romero-Isart , Gerhard Kirchmair

The question whether quantum mechanics is complete and the nature of the transition between quantum mechanics and classical mechanics have intrigued physicists for decades. There have been many experimental breakthroughs in creating larger…

Quantum Physics · Physics 2017-04-24 Zhang-qi Yin , Tongcang Li