English
Related papers

Related papers: Observable bound for Gaussian illumination

200 papers

Quantum metrology pursues high-precision measurements of physical quantities by using quantum resources. However, the decoherence generally hinders its performance. Previous work found that the metrological error tends to diverge in the…

Quantum Physics · Physics 2021-11-04 Wei Wu , Jun-Hong An

Better versions of separability conditions for four mode optical fields, i.e. two beams with two modes of mutually orthogonal polarization are given. Our conditions involve variances. Their meaning is intuitive and their implementation is…

Quantum Physics · Physics 2023-07-06 Bianka Woloncewicz , Tamoghna Das , Marek Żukowski

We address the limit of the Gaussian operations and classical communication in the problem of quantum state discrimination. We show that the optimal Gaussian strategy for the discrimination of the binary phase shift keyed (BPSK) coherent…

Quantum Physics · Physics 2009-11-13 Masahiro Takeoka , Masahide Sasaki

Quantum-enhanced sensing has a goal of enhancing a parameter sensitivity with input quantum states, while quantum illumination has a goal of enhancing a target detection capability with input entangled states in a heavy noise environment.…

Quantum Physics · Physics 2021-01-21 Su-Yong Lee , Yong Sup Ihn , Zaeill Kim

For more than a century, the diffraction limit has defined the resolution achievable by passive optical imaging systems. Although some resolution improvement can be gained through classical data processing of the image, it is limited by the…

Quantum Physics · Physics 2026-05-12 A. I. Lvovsky , Michael R. Grace , Saikat Guha , Mankei Tsang , Gerardo Adesso , Nicolas Treps

We address potential deviations of radiation field from the bosonic behaviour and employ local quantum estimation theory to evaluate the ultimate bounds to precision in the estimation of these deviations using quantum-limited measurements…

Quantum Physics · Physics 2014-07-09 Giovanni De Cillis , Matteo G. A. Paris

We show that the positivity of the Wigner function of Gaussian states and measurements provides an elegant way to bound the discriminating power of "linear optics", which we formalise as Gaussian measurement operations augmented by…

Quantum Physics · Physics 2021-02-03 Krishna Kumar Sabapathy , Andreas Winter

The quantum statistical fluctuations of the electromagnetic field establish a limit, known as the shot-noise limit, on the sensitivity of optical measurements performed with classical technologies. However, quantum technologies are not…

Quantum reading aims at retrieving classical information stored in an optical memory with low energy and high accuracy by exploiting the inherently quantum properties of light. We provide an optimal Gaussian strategy for quantum reading…

Quantum Physics · Physics 2013-02-08 Michele Dall'Arno

Quantum illumination employs entangled states to detect a weakly reflective target in a thermal bath. The performance of a given entangled state is evaluated from the minimum error probability in the asymptotic limit, which is compared…

Quantum Physics · Physics 2021-10-14 Changsuk Noh , Changhyoup Lee , Su-Yong Lee

Quantum non-Gaussian states of photons and phonons are conclusive and direct witnesses of higher-than-quadratic nonlinearities in optical and mechanical processes. Moreover, they are proven resources for quantum sensing, communication and…

Quantum Physics · Physics 2025-03-14 Lukáš Lachman , Radim Filip

Quantum optical metrology aims to identify ultimate sensitivity bounds for the estimation of parameters encoded into quantum states of the electromagnetic field. In many practical applications, including imaging, microscopy, and remote…

Quantum Physics · Physics 2023-02-15 Giacomo Sorelli , Manuel Gessner , Nicolas Treps , Mattia Walschaers

Loss measurements are at the base of spectroscopy and imaging, thus perme- ating all the branches of science, from chemistry and biology to physics and material science. However, quantum mechanics laws set the ultimate limit to the…

Quantum Physics · Physics 2018-05-17 Elena Losero , Ivano Ruo-Berchera , Alice Meda , Alessio Avella , Marco Genovese

We analyze the fundamental quantum limit of the resolution of an optical imaging system from the perspective of the detection problem of deciding whether the optical field in the image plane is generated by one incoherent on-axis source…

Quantum Physics · Physics 2018-12-10 Xiao-Ming Lu , Hari Krovi , Ranjith Nair , Saikat Guha , Jeffrey H. Shapiro

In quantum metrology, it is widely believed that the quantum Cramer-Rao bound is attainable bound while it is not true. In order to clarify this point, we explain why the quantum Cramer-Rao bound cannot be attained geometrically. In this…

Quantum Physics · Physics 2016-06-27 Masahito Hayashi , Sai Vinjanampathy , L. C. Kwek

A core problem in communications is the optimal discrimination of binary-phase-shift-keyed (BPSK) signals. A longstanding goal has been to reach the fundamental quantum limit, known as the Helstrom bound, for BPSK signals encoded in…

The impossibility of perfectly discriminating non orthogonal quantum states imposes far-reaching consequences both on quantum and classical communication schemes. We propose and numerically analyze an optimized quantum receiver for the…

Quantum Physics · Physics 2015-04-02 Christian R. Müller , Christoph Marquardt

We propose a novel protocol for quantum illumination: a quantum-enhanced noise radar. A two-mode squeezed state, which exhibits continuous-variable entanglement between so-called signal and idler beams, is used as input to the radar system.…

Quantum Physics · Physics 2019-07-08 C. W. Sandbo Chang , A. M. Vadiraj , J. Bourassa , B. Balaji , C. M. Wilson

In this article, the basic principle of target detection based on Gaussian state quantum illumination (QI) has introduced. The performance of such system has compared with its classical counterpart, which employs the most classical state of…

Quantum Physics · Physics 2021-08-24 Hossein Allahverdi , M. H. Qamat , M. Nowshadi

We investigate how distinguishability of a "noise" particle degrades interference of the "signal" particle. The signal, represented by an equatorial state of a photonic qubit, is mixed with noise, represented by another photonic qubit, via…

Quantum Physics · Physics 2013-08-16 Miroslav Gavenda , Lucie Celechovska , Jan Soubusta , Miloslav Dusek , Radim Filip