English
Related papers

Related papers: Operational Quantum Average-Case Distances

200 papers

The advent of quantum computers has significantly challenged the security of traditional cryptographic systems, prompting a surge in research on quantum key distribution (QKD). Among various QKD approaches, continuous-variable QKD (CVQKD)…

Quantum Physics · Physics 2025-03-26 Xiaojuan Liao , Yuehan Xu , Qijun Zhang , Peng Huang , Tao Wang , Kaizhi Wang , Guihua Zeng

A protocol with the potential of beating the existing distance records for conventional quantum key distribution (QKD) systems is proposed. It borrows ideas from quantum repeaters by using memories in the middle of the link, and that of…

Quantum Physics · Physics 2014-09-02 Christiana Panayi , Mohsen Razavi , Xiongfeng Ma , Norbert Lütkenhaus

Measurement is of central interest in quantum mechanics as it provides the link between the quantum world and the world of everyday experience. One of the features of the latter is its robust, objective character, contrasting the delicate…

Quantum Physics · Physics 2017-12-19 J. K. Korbicz , E. A. Aguilar , P. Ćwikliński , P. Horodecki

We introduce a tunable framework for generalized quantum state discrimination (GSD) and apply it to quantum key distribution (QKD) through a protocol we call phiQKD. Building upon the two-state B92 protocol, phiQKD replaces the traditional…

Quantum key distribution relying on the principles of quantum mechanics enables two parties to produce a shared random secret key, thereby ensuring the security of data transmission. Continuous variable quantum key distribution (CV-QKD) is…

Quantum Physics · Physics 2025-03-05 Dengke Qi , Xiangyu Wang , Jiayu Ma , Zhenghua Li , Ziyang Chen , Yueming Lu , Song Yu

Performance of quantum teleportation is typically measured by the average fidelity, an overlap between the input and output states. Along with the first moment, we introduce the second moment of fidelity in CV teleportation, i.e., the…

Quantum Physics · Physics 2022-09-16 Ayan Patra , Rivu Gupta , Saptarshi Roy , Aditi Sen De

A continuous variable (CV), measurement device independent (MDI) quantum key distribution (QKD) protocol is analyzed, enabling three parties to connect for quantum conferencing. We utilise a generalised Bell detection at an untrusted relay…

Quantum Physics · Physics 2022-10-19 Alasdair I. Fletcher , Stefano Pirandola

We present a general model on the simulation of the measurement-device independent quantum key distribution (MDI-QKD). It can be used to predict experimental observations of a MDI-QKD with linear channel loss, simulating corresponding…

Quantum Physics · Physics 2013-12-03 Qin Wang , Xiang-Bin Wang

Recently, a protocol for quantum state discrimination (QSD) in a multi-party scenario has been introduced [Phys. Rev. Lett. 111, 100501 (2013)]. In this protocol, Alice generates a quantum system in one of two pre-defined non-orthogonal…

Quantum Physics · Physics 2016-10-11 M. A. Solís-Prosser , P. González , J. Fuenzalida , S. Gómez , G. B. Xavier , A. Delgado , G. Lima

Fault-tolerant quantum computation requires non-destructive quantum measurements with classical feed-forward. Many experimental groups are actively working towards implementing such capabilities and so they need to be accurately evaluated.…

Quantum Physics · Physics 2023-06-14 Darian McLaren , Matthew A. Graydon , Joel J. Wallman

Quantum technologies exploit entanglement to enhance various tasks beyond their classical limits including computation, communication and measurements. Quantum metrology aims to increase the precision of a measured quantity that is…

Quantum Physics · Physics 2020-08-25 Bálint Koczor , Suguru Endo , Tyson Jones , Yuichiro Matsuzaki , Simon C. Benjamin

Measuring the distinguishability between quantum states is a basic problem in quantum information theory. In this paper, we develop optimal quantum algorithms that estimate both the trace distance and the (square root) fidelity between pure…

Quantum Physics · Physics 2024-11-27 Qisheng Wang

We propose and analyze continuous measurements of atom number and atomic currents using dispersive probing in an optical cavity. For an atom-number measurement in a closed system, we relate both the detection noise and the heating rate due…

Quantum Gases · Physics 2018-12-18 Shun Uchino , Masahito Ueda , Jean-Philippe Brantut

We propose and experimentally implement a novel reconfigurable quantum key distribution (QKD) scheme, where the users can switch in real time between conventional QKD and the recently-introduced measurement-device-independent (MDI) QKD.…

Continuous-variable quantum key distribution (CV-QKD) enables two remote parties to establish information-theoretically secure keys and offers high practical feasibility due to its compatibility with mature coherent optical communication…

Quantum Physics · Physics 2025-12-18 Yanhao Sun , Jiayu Ma , Xiangyu Wang , Song Yu , Ziyang Chen , Hong Guo

A theoretical research and numerical simulation of the noise influence caused by spontaneous Raman scattering, four-wave mixing, and linear channel crosstalk on the performance of QKD systems was conducted. Three types of QKD systems were…

Quantum Physics · Physics 2023-05-18 Irina Vorontsova , Roman Goncharov , Angelina Tarabrina , Fedor Kiselev , Vladimir Egorov

The total variation distance is a metric of central importance in statistics and probability theory. However, somewhat surprisingly, questions about computing it algorithmically appear not to have been systematically studied until very…

Data Structures and Algorithms · Computer Science 2025-03-17 Arnab Bhattacharyya , Weiming Feng , Piyush Srivastava

Quantum correlations in a composite system can be measured by resorting to a geometric approach, according to which the distance from the state of the system to a suitable set of classically correlated states is considered. Here we show…

Quantum Physics · Physics 2015-06-10 Marco Cianciaruso , Thomas R. Bromley , Wojciech Roga , Rosario Lo Franco , Gerardo Adesso

The distance between a quantum state and its closest state not having a certain property has been used to quantify the amount of correlations corresponding to that property. This approach allows a unified view of the various kinds of…

We introduce a measure of average dimensionality (or coherence) for high-dimensional quantum devices. This includes sets of quantum measurements, steering assemblages, and quantum channels. For measurements and channels, our measure…

Quantum Physics · Physics 2023-06-22 Thomas Cope , Roope Uola