English
Related papers

Related papers: Protecting the quantum interference of cat states …

200 papers

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

Bosonic codes, leveraging infinite-dimensional Hilbert spaces for redundancy, offer great potential for encoding quantum information. However, the realization of a practical continuous-variable bosonic code that can simultaneously correct…

Quantum Physics · Physics 2026-05-19 Yexiong Zeng , Fernando Quijandría , Clemens Gneiting , Franco Nori

Disposing of simple and efficient sources for photonic states with non-classical photon statistics is of paramount importance for implementing quantum computation and communication protocols. In this work, we propose an innovative approach…

Quantum Physics · Physics 2023-05-03 M. F. Melalkia , J. Huynh , S. Tanzilli , V. D'Auria , J. Etesse

These are the lecture notes from the 2019 Les Houches Summer School on "Quantum Information Machines". After a brief introduction to quantum error correction and bosonic codes, we focus on the case of cat qubits stabilized by a nonlinear…

Quantum Physics · Physics 2023-06-14 Jérémie Guillaud , Joachim Cohen , Mazyar Mirrahimi

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

Quantum-enhanced measurements hold the promise to improve high-precision sensing ranging from the definition of time standards to the determination of fundamental constants of nature. However, quantum sensors lose their sensitivity in the…

Quantum Physics · Physics 2018-01-11 F. Reiter , A. S. Sørensen , P. Zoller , C. A. Muschik

Quantum computing allows for the manipulation of highly correlated states whose properties quickly go beyond the capacity of any classical method to calculate. Thus one natural problem which could lend itself to quantum advantage is the…

Quantum Physics · Physics 2024-12-19 Kevin Lively , Tim Bode , Jochen Szangolies , Jian-Xin Zhu , Benedikt Fauseweh

We analyze generalized Gaussian cat states obtained by superposing arbitrary Gaussian states, e.g., a coherent state and a squeezed state. The Wigner functions of such states exhibit the typical pair of Gaussian hills plus an interference…

Quantum Physics · Physics 2015-05-18 Fernando Nicacio , Raphael N. P. Maia , Fabricio Toscano , Raul O. Vallejos

Recent results have established dramatic advantages in learning properties of quantum states when a quantum computer is available to process or jointly measure multiple copies of the unknown quantum state. Learning tasks can be accomplished…

Quantum Physics · Physics 2026-05-08 Spencer Dimitroff , John Kallaugher , Ashe Miller , Mohan Sarovar

Multi-mode NOON states can quantum-enhance multiple-phase estimation in the absence of photon loss. However, a multi-mode NOON state is known to be vulnerable to photon loss, and its quantum-enhancement can be dissipated by lossy…

Quantum Physics · Physics 2024-07-23 Min Namkung , Dong-Hyun Kim , Seongjin Hong , Yong-Su Kim , Changhyoup Lee , Hyang-Tag Lim

Continuous-variable quantum systems are foundational to quantum computation, communication, and sensing. While traditional representations using wave functions or density matrices are often impractical, the tomographic picture of quantum…

Quantum Physics · Physics 2026-03-17 Liubov A. Markovich , Xiaoyu Liu , Jordi Tura

The ability to protect quantum information from the effect of noise is one of the major goals of quantum information processing. In this article, we study limitations on the asymptotic stability of quantum information stored in passive…

Quantum Physics · Physics 2010-10-19 Fernando Pastawski , Alastair Kay , Norbert Schuch , Ignacio Cirac

In this letter, first, we investigate the security of a continuous-variable quantum cryptographic scheme with a postselection process against individual beam splitting attack. It is shown that the scheme can be secure in the presence of the…

Quantum Physics · Physics 2009-11-10 Ryo Namiki , Takuya Hirano

We demonstrate squeezing of a strongly interacting opto-electromechanical system using a parametric drive. By employing real-time feedback on the phase of the pump at twice the resonance frequency the thermo-mechanical noise is squeezed…

Optics · Physics 2014-12-09 Menno Poot , King Y. Fong , Hong X. Tang

Generation of high fidelity photonic non-Gaussian states is a crucial ingredient for universal quantum computation using continous-variable platforms, yet it remains a challenge to do so efficiently. We present a general framework for a…

Quantum Physics · Physics 2019-11-06 Daiqin Su , Casey R. Myers , Krishna Kumar Sabapathy

General purpose quantum computers can, in principle, entangle a number of noisy physical qubits to realise composite qubits protected against errors. Architectures for measurement-based quantum computing intrinsically support…

We investigate how resourceful gravitational cat states are to preserve quantum correlations. In this regard, we explore the dynamics of gravitational cat states under different situations such as thermal, classical stochastic, general…

Quantum Physics · Physics 2025-11-25 Atta ur Rahman , Ao-Xiang Liu , Saeed Haddadi , Cong-Feng Qiao

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

Quantum computing holds the promise of solving classically intractable problems. Enabling this requires scalable and hardware-efficient quantum processors with vanishing error rates. This perspective manuscript describes how bosonic codes,…

Bosonic fault tolerant quantum computing requires preparations of Bosonic code states like cat states and GKP states with high fidelity and reliable quantum certification of these states. Although many proposals on preparing these states…

Quantum Physics · Physics 2022-12-01 Ya-Dong Wu