English
Related papers

Related papers: Experimental characterisation of unsharp qubit obs…

200 papers

The quantum measurement incompatibility is a distinctive feature of quantum mechanics. We investigate the incompatibility of a set of general measurements and classify the incompatibility by the hierarchy of compatibilities of its subsets.…

Quantum Physics · Physics 2020-02-03 Bao-Zhi Sun , Zhi-Xi Wang , Xianqing Li-Jost , Shao-Ming Fei

We address the problem of whether parties who cannot communicate but share nonsignaling quantum correlations between the outcomes of sharp measurements can distinguish, just from the value of a correlation observable, whether their outcomes…

Quantum Physics · Physics 2017-07-24 Zhen-Peng Xu , Adan Cabello

We investigate the optimal approximation to triple incompatible quantum measurements within the framework of statistical distance and joint measurability. According to the lower bound of the uncertainty inequality presented in [Physical…

Quantum Physics · Physics 2022-06-01 Hui-Hui Qin , Shao-Ming Fei

In this letter we study the weak-convergence properties of random variables generated by unsharp quantum measurements. More precisely, for a sequence of random variables generated by repeated unsharp quantum measurements, we study the limit…

Quantum Physics · Physics 2020-08-12 Aleksandra Dimić , Borivoje Dakić

This paper addresses the question whether a variant of a modal interpretation is conceivable that could accommodate property ascriptions associated with nonorthogonal resolutions of the unity and nonorthogonal families of relative states as…

Quantum Physics · Physics 2007-05-23 P. Busch

In this work we give a $(n,n)$-threshold protocol for sequential secret sharing of quantum information for the first time. By sequential secret sharing we refer to a situation where the dealer is not having all the secrets at the same time,…

Quantum Physics · Physics 2016-08-11 Maharshi Ray , Sourav Chatterjee , Indranil Chakrabarty

We present a protocol in which sequential weak measurements of a quantum harmonic oscillator enable simultaneous estimation of both quadratures of a displacement channel. Calculations of the quantum Fisher information show that the…

Quantum Physics · Physics 2026-05-04 Koray Mentesoglu , Rahul Trivedi , Sara Mouradian

We present a new quantum communication complexity protocol, the promise--Quantum Random Access Code, which allows us to introduce a new measure of unbiasedness for bases of Hilbert spaces. The proposed measure possesses a clear operational…

Quantum Physics · Physics 2018-08-08 Edgar A. Aguilar , Jakub J. Borkała , Piotr Mironowicz , Marcin Pawłowski

Quantum coherence is the key resource for quantum technology, with applications in quantum optics, information processing, metrology and cryptography. Yet, there is no universally efficient method for quantifying coherence either in…

Quantum Physics · Physics 2014-10-24 Davide Girolami

When an experimentalist measures a time series of qubits, the outcomes generate a classical stochastic process. We show that measurement induces high complexity in these processes in two specific senses: they are inherently unpredictable…

Quantum Physics · Physics 2020-10-14 Ariadna E. Venegas-Li , Alexandra M. Jurgens , James P. Crutchfield

The problem of noise incidence on qubits taking part of bipartite entanglement-based protocols is addressed. It is shown that the use of a three-partite GHZ state and measurements instead of their EPR counterparts allows the experimenter to…

Quantum Physics · Physics 2018-09-10 M. G. M. Moreno , Alejandro Fonseca , Márcio M. Cunha

We discuss sequential unambiguous state-discrimination measurements performed on the same qubit. Alice prepares a qubit in one of two possible states. The qubit is first sent to Bob, who measures it, and then on to Charlie, who also…

Quantum Physics · Physics 2015-06-16 Janos Bergou , Edgar Feldman , Mark Hillery

Multiple observers who independently harvest nonclassical correlations from a single physical system share the system's ability to enable quantum correlations. We show that any number of independent observers can share the preparation…

The ability to transfer coherent quantum information between systems is a fundamental component of quantum technologies and leads to coherent correlations within the global quantum process. However correlation structures in quantum channels…

Quantum Physics · Physics 2022-05-03 Matthew Girling , Cristina Cirstoiu , David Jennings

The quantum variables that can be accessed directly by experiments are described by observables. Therefore, physical parameters can only be evaluated indirectly, via estimations based on experimental measurement results. I show that the…

Quantum Physics · Physics 2012-12-12 B. M. Escher

We propose a protocol for countering the effects of dephasing in quantum state transfer over a noisy spin channel weakly coupled to the sender and receiver qubits. Our protocol, based on performing regular global measurements on the…

Quantum Physics · Physics 2015-10-26 Abolfazl Bayat , Yasser Omar

A generic qubit unitary operator affected by quantum noise is duplicated and inserted in a coherently superposed channel, superposing two paths offered to a probe qubit across the noisy unitary, and driven by a control qubit. A…

Quantum Physics · Physics 2021-10-14 Francois Chapeau-Blondeau

Increasingly sophisticated programmable quantum simulators and quantum computers are opening unprecedented opportunities for exploring and exploiting the properties of highly entangled complex quantum systems. The complexity of large…

The generation of certifiable randomness is one of the most promising applications of quantum technologies. Furthermore, the intrinsic non-locality of quantum correlations allow us to certify randomness in a device-independent way, i.e. one…

Quantum Physics · Physics 2020-08-04 Brian Coyle , Elham Kashefi , Matty Hoban

Programmable photonic quantum processors face a critical challenge: despite significant advances in quantum state preparation and manipulation, measurements remain limited to projective techniques. Here, we demonstrate a programmable…