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Related papers: Coherent-state phase concentration by quantum prob…

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We investigate the superposition of coherent states, emphasizing quantum states with distinct Wigner phase-space features relevant to quantum information applications. In this study, we introduce generalized versions of the compass state,…

Quantum Physics · Physics 2025-08-26 Tan Hailin , Naeem Akhtar , Gao Xianlong

We present a scheme of quantum state truncation in the Fock basis (quantum scissors), based on the combined action of a nondegenerate optical parametric amplifier and a beamsplitter. Differently from previously proposed linear-optics-based…

Quantum Physics · Physics 2021-10-05 E. P. Mattos , A. Vidiella-Barranco

Estimation of the properties of a physical system with minimal uncertainty is a central task in quantum metrology. Optical phase estimation is at the center of many metrological tasks where the value of a physical parameter is mapped to the…

Quantum Physics · Physics 2020-09-29 M. T. DiMario , F. E. Becerra

Based on phase-space structures of quantum states, we propose a novel measure to quantify macroscopic quantum superpositions. Our measure simultaneously quantifies two different kinds of essential information for a given quantum state in a…

Quantum Physics · Physics 2011-06-02 Chang-Woo Lee , Hyunseok Jeong

Here we are investigating the enhancement in phase sensitivity and resolution in Mach-Zehnder interferometer (MZI) based quantum LiDAR. We are using multi-photonic state (MPS), superposition of four coherent states [1], as the input state…

Quantum Physics · Physics 2024-04-04 Priyanka Sharma , Manoj K. Mishra , Devendra Kumar Mishra

We report a theoretical study of a quantum optical model consisting of an array of strongly nonlinear cavities incoherently pumped by an ensemble of population-inverted two-level atoms. Projective methods are used to eliminate the atomic…

Quantum Gases · Physics 2016-09-21 José Lebreuilly , Iacopo Carusotto , Michiel Wouters

We investigated precision measurements in a two-level system coupled to a single-photon-added coherent state (SPACS) under postselection measurement. We analyzed strategies for improving measurement precision, including parameter estimation…

Quantum Physics · Physics 2025-05-13 Yi-Fang Ren , Yusuf Turek

Using coherent phase states, parameterized phase state distributions for a single-mode radiation field are introduced and their integral relation to the phase-parameterized field-strength distributions is studied. The integral kernel is…

Quantum Physics · Physics 2008-02-03 M. Dakna , L. Knoll , D. -G. Welsch

The use of distributed amplifiers may have some potential advantages for the transmission of quantum information through optical fibers. In addition to the quantum noise introduced by the amplifiers, entanglement between atoms in the…

Quantum Physics · Physics 2015-11-26 J. D. Franson , B. T. Kirby

Quantum entanglement offers the possibility of making measurements beyond the classical limit, however some issues still need to be overcome before it can be applied in realistic lossy systems. Recent work has used the quantum Fisher…

Quantum Physics · Physics 2014-01-17 P. A. Knott , J. A. Dunningham

We present an experimental realization of a low-noise, phase-insensitive optical amplifier using a four-wave mixing interaction in hot Rb vapor. Performance near the quantum limit for a range of amplifier gains, including near unity, can be…

Quantum Physics · Physics 2015-05-13 R. C. Pooser , A. M. Marino , V. Boyer , K. M. Jones , P. D. Lett

The production of conditional quantum states and quantum operations based on the result of measurement is now seen as a key tool in quantum information and metrology. We propose a new type of photon number detector. It functions…

Quantum Physics · Physics 2009-11-10 A. M. Branczyk , Tobias J. Osborne , Alexei Gilchrist , T. C. Ralph

In this paper, we investigate the problem of estimating the phase of a coherent state in the presence of unavoidable noisy quantum states. These unwarranted quantum states are represented by outlier quantum states in this study. We first…

Quantum Physics · Physics 2020-08-06 Yukito Mototake , Jun Suzuki

Interference of light fields plays an important role in various high-precision measurement schemes. It has been shown that super resolving phase measurements beyond the standard coherent state limit can be obtained either by using maximally…

Quantum Physics · Physics 2013-10-08 Emanuele Distante , Miroslav Jezek , Ulrik L. Andersen

Loss and decoherence are a major problem in the transmission of non-classical states of light over large distances. It was recently shown that the effects of decoherence can be reduced by applying a probabilistic noiseless attenuator before…

Quantum Physics · Physics 2018-09-19 R. A. Brewster , T. B. Pittman , J. D. Franson

We introduce the first method to enable an optical amplification of a coherent Raman spectroscopy signal called radio frequency Doppler Raman spectroscopy. Doppler Raman measurements amplify the optical signals in coherent Raman…

Single photons provide excellent quantum information carriers, but current schemes for preparing, processing and measuring them are inefficient. For example, down-conversion provides heralded, but randomly timed single photons, while…

Quantum Physics · Physics 2012-02-07 N. K. Langford , S. Ramelow , R. Prevedel , W. J. Munro , G. J. Milburn , A. Zeilinger

We predict a novel effect in a quantum two-level system (TLS) coupled to a resonant cavity. By bringing the TLS in and out of resonance with the cavity by a series of $N$ rectangular bias pulses (the length of the $m$th pulse scaling as…

Other Condensed Matter · Physics 2009-11-10 A. M. Zagoskin , M. Grajcar , A. N. Omelyanchouk

We propose and analyze a multi-functional setup consisting of high finesse optical cavities, beam splitters, and phase shifters. The basic scheme projects arbitrary photonic two-mode input states onto the subspace spanned by the product of…

Quantum Physics · Physics 2015-03-13 Anne E. B. Nielsen , Christine A. Muschik , Geza Giedke , K. G. H. Vollbrecht

Multiple-phase estimation exploiting quantum states has broad applications in novel sensing and imaging technologies. However, the unavoidable presence of lossy environments in practical settings often diminishes the precision of phase…

Quantum Physics · Physics 2025-07-23 Min Namkung , Dong-Hyun Kim , Seongjin Hong , Changhyoup Lee , Hyang-Tag Lim