English
Related papers

Related papers: Discriminating qubit amplitude damping channels

200 papers

Quantum illumination is a protocol for detecting a low-reflectivity target by using two-mode entangled states composed of signal and idler modes, which can outperform unentangled states. We study multi-qudit states for single-shot detection…

Quantum Physics · Physics 2026-01-01 Sunghwa Kang , Yonggi Jo , Jihwan Kim , Zaeill Kim , Duk Y. Kim , Su-Yong Lee

Entanglement behavior for different classes of two qubit systems passing through a generalized amplitude damping channel is discussed. The phenomena of sudden single, double changes and the sudden death of entanglement are reported for…

Quantum Physics · Physics 2015-06-18 Nasser Metwally

The idea of exploiting maximally-entangled states as a resource lies at the core of several modalities of quantum information processing, including secure quantum communication, quantum computation, and quantum sensing. However, due to…

Quantum Physics · Physics 2023-05-31 Andrea Rodriguez-Blanco , K. Birgitta Whaley , Alejandro Bermudez

For carrying out many quantum information protocols entanglement must be established in advance between two distant parties. Practically, inevitable interaction of entangled subsystems with their environments during distribution and storage…

Quantum Physics · Physics 2015-01-19 Xin-Wen Wang , Shi-Qing Tang , Ji-Bing Yuan , Le-Man Kuang

Probabilistic quantum filtering is proposed to properly adapt sequential independent quantum channels in order to stop sudden death of entanglement. In the adaptation, the quantum filtering does not distill or purify more entanglement, it…

Quantum Physics · Physics 2009-05-07 Miroslav Gavenda , Radim Filip

We investigate strategies for estimating a depolarizing channel for a finite dimensional system. Our analysis addresses the double optimization problem of selecting the best input probe state and the measurement strategy that minimizes the…

Quantum Physics · Physics 2009-11-07 Masahide Sasaki , Masashi Ban , Stephen M. Barnett

I investigate the problem of optimally discriminating between two open quantum dynamical processes in a single-shot scenario, with the goal of minimizing the error probability of identification. This task involves optimising both the input…

Quantum Physics · Physics 2025-12-10 Massimiliano F. Sacchi

Quantification of entanglement against mixing is given for a system of coupled qubits under a phase damping channel. A family of pure initial joint states is defined, ranging from pure separable states to maximally entangled state. An…

Quantum Physics · Physics 2009-11-11 E. S. Cardoso , M. C. de Oliveira , K. Furuya

Entangled inputs can enhance the capacity of quantum channels, this being one of the consequences of the celebrated result showing the non-additivity of several quantities relevant for quantum information science. In this work, we answer…

Quantum Physics · Physics 2015-05-20 Fernando G. S. L. Brandao , Jens Eisert , Michal Horodecki , Dong Yang

We re-examine a non-Gaussian quantum error correction code designed to protect optical coherent-state qubits against errors due to an amplitude damping channel. We improve on a previous result [Phys. Rev. A 81, 062344 (2010)] by providing a…

Quantum Physics · Physics 2014-05-14 Ricardo Wickert , Peter van Loock

We address the use of entanglement to improve the precision of generalized quantum interferometry, i.e. of binary measurements aimed to determine whether or not a perturbation has been applied by a given device. For the most relevant…

Quantum Physics · Physics 2007-05-23 G. M. D'Ariano , Matteo G. A Paris , Paolo Perinotti

Shared entanglement can significantly amplify classical correlations between systems interacting over a limited quantum channel. A natural avenue is to use entanglement of the same dimension as the channel because this allows for unitary…

Distinguishing physical processes is one of the fundamental problems in quantum physics. Although distinguishability of quantum preparations and quantum channels have been studied considerably, distinguishability of quantum measurements…

Quantum Physics · Physics 2021-04-13 Chandan Datta , Tanmoy Biswas , Debashis Saha , Remigiusz Augusiak

We study discrimination of m quantum measurements in the scenario when the unknown measurement with n outcomes can be used only once. We show that ancilla-assisted discrimination procedures provide a nontrivial advantage over simple…

Quantum Physics · Physics 2014-12-01 Michal Sedlak , Mario Ziman

We study the dynamics of two qubits separately sent through two coupled resonators, each initially containing a coherent state field. We present analytical arguments and numerical calculations for the qubit-field system under different…

Quantum Physics · Physics 2015-06-18 Li-Tuo Shen , Rong-Xin Chen , Huai-Zhi Wu , Zhen-Biao Yang

In this paper, the following scenario is considered: there are two qubits possessed by two parties at different locations. Qubits have been prepared in one of a maximum of four, mutually-orthogonal, entangled states and the parties wish to…

Quantum Physics · Physics 2016-09-29 Özenç Güngör , Sadi Turgut

We present two method for optimal entanglement concentration from pure entangled states by local actions only. However a prior knowledge of the Schmidt coefficients is required. The first method is optimally efficient only when a finite…

Quantum Physics · Physics 2009-10-31 Somshubhro Bandyopadhyay

We have proposed a scheme of the generation and preservation of two-qubit steady state quantum correlations through quantum channels where successive uses of the channels are correlated. Different types of noisy channels with memory, such…

Quantum Physics · Physics 2016-04-15 You-neng Guo , Mao-fa Fang , Guo-you Wang , Ke Zeng

Quantum entanglement is a crucial resource in quantum information processing, and protecting it against noise poses a significant challenge. This paper introduces two strategies for preserving qutrit-qutrit entanglement in the presence of…

Quantum Physics · Physics 2026-04-24 Xing Xiao , Wen-Rui Huang , Tian-Xiang Lu , Yan-Ling Li

Experimental determination of entanglement is important not only to characterize the state and use it in quantum information, but also in understanding complicated phenomena such as phase transitions. In this paper we show that in many…

Quantum Physics · Physics 2016-01-20 Gaurav Chaudhary , V. Ravishankar