English
Related papers

Related papers: Effective squeezing enhancement via measurement-in…

200 papers

Entanglement distillation is a fundamental building block in long-distance quantum communication. Though known to be useless on their own for distilling Gaussian entangled states, local Gaussian operations may still help to improve…

Quantum Physics · Physics 2013-05-29 ShengLi Zhang , Peter van Loock

We find and investigate the optimal scheme of quantum distributed Gaussian sensing for estimation of the average of independent phase shifts. We show that the ultimate sensitivity is achievable by using an entangled symmetric Gaussian…

Quantum Physics · Physics 2020-04-14 Changhun Oh , Changhyoup Lee , Seok Hyung Lie , Hyunseok Jeong

We study an experimental scheme to generate Gaussian two-mode entangled states via beam splitter. Specifically, we consider a nonclassical Gaussian state (squeezed state) and a thermal state as two input modes, and evaluate the degree of…

Quantum Physics · Physics 2009-11-13 Rabia Tahira , Manzoor Ikram , Hyunchul Nha , M. Suhail Zubairy

Entangled two-mode Gaussian states constitute an important building block for continuous variable quantum computing and communication protocols. In this work, we theoretically study two-mode bipartite states which are extracted from…

Quantum Physics · Physics 2026-01-21 Denis A. Kopylov , Torsten Meier , Polina R. Sharapova

Nonlinear squeezing is a property of non-Gaussian states of light with an important application in continuous variable quantum computing. We study the generation of nonlinear squeezing in multimode systems produced by the photon-added…

Quantum Physics · Physics 2025-05-15 Vojtěch Kala , Denis Kopylov , Petr Marek , Polina Sharapova

We study nonclassical correlations beyond entanglement in a family of two-mode non-Gaussian states which represent the continuous-variable counterpart of two-qubit Werner states. We evaluate quantum discord and other quantumness measures…

Quantum Physics · Physics 2015-06-03 Richard Tatham , Ladislav Mišta , Gerardo Adesso , Natalia Korolkova

In this work we focus on evaluating the effectiveness of two non-Gaussian operations, photon subtraction (PS) and quantum scissors (QS) in terms of Continuous Variable (CV)-Quantum Key Distribution (QKD) over lossy channels. Each operation…

Quantum Physics · Physics 2020-07-21 Eduardo Villaseñor , Robert Malaney

Local unitary transforms cannot affect the quantum correlations between two systems sharing an entangled state although they do influence the outcomes of local measurements. By considering local squeezing operations we introduce an extended…

Quantum Physics · Physics 2023-11-15 A. Lezama , A. Auyuanet

Genuine multimode entanglement in continuous variable systems can be quantified by exploring the geometry of the state-space, namely via the generalized geometric measure (GGM) which is defined as the shortest distance of a given multimode…

Quantum Physics · Physics 2020-07-22 Saptarshi Roy , Tamoghna Das , Aditi Sen De

Entanglement had played a crucial role in developing frontier technologies as a critical resource, for instance, in quantum teleportation and quantum sensing schemes. Notably, thanks to the ability to cool down the vibrational modes of…

Quantum Physics · Physics 2022-03-03 Gentil Dias de Moraes Neto , Victor Montenegro

We introduce a protocol for generating a broad class of non-Gaussian (nG) quantum states via postselected weak measurement techniques. The scheme involves injecting an arbitrary quantum state and a single photon into the signal and idler…

Quantum Physics · Physics 2025-12-29 Xiao-Xi Yao , Yusuf Turek

We present a multimode theory of non-Gaussian operation induced by an imperfect on/off-type photon detector on a splitted beam from a wideband squeezed light. The events are defined for finite time duration $T$ in the time domain. The…

Quantum Physics · Physics 2009-11-11 M. Sasaki , S. Suzuki

Very recently, strongly non-Gaussian states have been observed via a direct three-mode spontaneous parametric down-conversion in a superconducting cavity [Phys. Rev. X 10, 011011 (2020)]. The created multi-photon non-Gaussian correlations…

Quantum Physics · Physics 2022-08-26 Mingsheng Tian , Yu Xiang , Feng-Xiao Sun , Matteo Fadel , Qiongyi He

Squeezed states of light are one of the most important fundamental resources for quantum optics, optical quantum information processing and quantum sensing. Recently, it has been experimentally demonstrated that the squeezing of single-mode…

Quantum Physics · Physics 2025-08-26 Jaromír Fiurášek , Stephan Grebien , Roman Schnabel

We describe the observation of a degaussification protocol that maps individual pulses of squeezed light onto non-Gaussian states. This effect is obtained by sending a small fraction of the squeezed vacuum beam onto an avalanche photodiode,…

Quantum Physics · Physics 2009-11-10 J. Wenger , R. Tualle-Brouri , P. Grangier

We study quantum correlations beyond entanglement in two-mode Gaussian states of continuous variable systems, by means of the measurement-induced disturbance (MID) and its ameliorated version (AMID). In analogy with the recent studies of…

Quantum Physics · Physics 2015-03-17 Ladislav Mišta, , Richard Tatham , Davide Girolami , Natalia Korolkova , Gerardo Adesso

Entanglement distillation is an essential ingredient for long distance quantum communications. In the continuous variable setting, Gaussian states play major roles in quantum teleportation, quantum cloning and quantum cryptography. However,…

Multiple photon subtraction applied to a displaced phase-averaged coherent state, which is a non-Gaussian classical state, produces conditional states with a non trivial (positive) Glauber-Sudarshan $P$-representation. We theoretically and…

Quantum Physics · Physics 2013-12-02 Stefano Olivares , Alessia Allevi , Maria Bondani

We introduce a feasible protocol for generating non-Gaussian (nG) states via postselected von Neumann measurement for continuous-variable quantum information processing. The method uses a two-level system coupled to a Gaussian pointer state…

Quantum Physics · Physics 2025-10-01 Xiao-Xi Yao , Yusuf Turek

Multipartite entangled states are significant resources for both quantum information processing and quantum metrology. In particular, non-Gaussian entangled states are predicted to achieve a higher sensitivity of precision measurements than…