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We introduce an operational and statistically meaningful measure, the quantum tomographic transfer function, that possesses important physical invariance properties for judging whether a given informationally complete quantum measurement…

Quantum Physics · Physics 2019-07-31 Jaroslav Rehacek , Yong Siah Teo , Zdenek Hradil

It is known that mutually unbiased bases, whenever they exist, are optimal in an information theoretic sense for the determination of unknown state of a quantum ensemble. These bases may not exist in most dimensions and some suboptimal…

Quantum Physics · Physics 2007-05-23 Manas Patra

We demonstrate a method for super-resolving signals encoded as finite mixtures of bosonic modes using collective measurements that exploit permutation symmetry. Specifically, we use multiple copies of the state $\rho$ of the finite mixture…

Quantum Physics · Physics 2025-11-06 J. O. de Almeida , M. Lewenstein , M. Skotiniotis

We define the geometric measure of mixing of quantum state as a minimal Hilbert-Schmidt distance between the mixed state and a set of pure states. An explicit expression for the geometric measure is obtained. It is interesting that this…

Quantum Physics · Physics 2018-09-27 H. P. Laba , V. M. Tkachuk

We initiate the study of sample-optimal quantum state tomography with minimal disturbance to the samples. Can we efficiently learn a precise description of a quantum state through sequential measurements of samples while at the same time…

Quantum Physics · Physics 2025-06-06 Josep Lumbreras , Mikhail Terekhov , Marco Tomamichel

We present a framework that formulates the quest for the most efficient quantum state tomography scheme as an optimization problem which can be solved numerically. This approach can be applied to a broad spectrum of relevant setups…

Quantum Physics · Physics 2021-12-17 Violeta N. Ivanova-Rohling , Guido Burkard , Niklas Rohling

We study quantum tomography based on a stochastic continuous-time measurement record obtained from a probe field collectively interacting with an ensemble of identically prepared systems. In comparison to previous studies, we consider here…

Quantum Physics · Physics 2014-10-01 Robert L. Cook , Carlos A. Riofrío , Ivan H. Deutsch

An efficient method for assessing the quality of quantum state tomography is developed. Special attention is paid to the tomography of multipartite systems in terms of unbiased measurements. Although the overall reconstruction errors of…

Quantum Physics · Physics 2013-11-19 J. Rehacek , Z. Hradil , A. B. Klimov , G. Leuchs , L. L. Sanchez-Soto

Measurement-based quantum computation (MBQC) represents a powerful and flexible framework for quantum information processing, based on the notion of entangled quantum states as computational resources. The most prominent application is the…

Quantum Physics · Physics 2014-05-26 B. P. Lanyon , P. Jurcevic , M. Zwerger , C. Hempel , E. A. Martinez , W. Dür , H. J. Briegel , R. Blatt , C. F. Roos

The paper deals with quantum pulse position modulation (PPM), both in the absence (pure states) and in the presence (mixed states) of thermal noise, using the Glauber representation of coherent laser radiation. The objective is to find…

Quantum Physics · Physics 2009-11-16 G. Cariolaro , G. Pierobon

We have investigated the problem of discriminating between nonorthogonal quantum states with least probability of error. We have determined that the best strategy for some sets of states is to make no measurement at all, and simply to…

Quantum Physics · Physics 2009-11-07 Kieran Hunter

We consider the statistical problem of `compressive' estimation of low rank states with random basis measurements, where the estimation error is expressed terms of two metrics - the Frobenius norm and quantum infidelity. It is known that…

Quantum Physics · Physics 2019-01-04 Anirudh Acharya , Madalin Guta

In this article, by treating minimum error state discrimination as a complementarity problem, we obtain the geometric optimality conditions. These can be used as the necessary and sufficient conditions to determine whether every optimal…

Quantum Physics · Physics 2015-06-17 Donghoon Ha , Younghun Kwon

The phenomenon of quantum steering in bipartite quantum systems can be reduced to the question whether or not the first party can perform measurements such that the conditional states on the second party can be explained by a local hidden…

Quantum Physics · Physics 2020-05-06 H. Chau Nguyen , Otfried Gühne

We consider the problem of designing a measurement to minimize the probability of a detection error when distinguishing between a collection of possibly non-orthogonal mixed quantum states. We show that if the quantum state ensemble…

Quantum Physics · Physics 2009-11-10 Yonina C. Eldar

Suppose you receive a sequence of qubits where each qubit is guaranteed to be in one of two pure states, but you do not know what those states are. Your task is to determine the states. This can be viewed as a kind of quantum state learning…

A quantum copying machine producing two (in general non-identical) copies of an arbitrary input state of a two-dimensional Hilbert space (qubit) is studied using a quality measure based on distinguishability of states, rather than fidelity.…

Quantum Physics · Physics 2009-10-31 Chi-Sheng Niu , Robert B. Griffiths

We develop a sufficient condition for the least-squares measurement (LSM), or the square-root measurement, to minimize the probability of a detection error when distinguishing between a collection of mixed quantum states. Using this…

Quantum Physics · Physics 2007-05-23 Yonina C. Eldar , Alexandre Megretski , George C. Verghese

A minimax estimator has the minimum possible error ("risk") in the worst case. We construct the first minimax estimators for quantum state tomography with relative entropy risk. The minimax risk of non-adaptive tomography scales as…

Quantum Physics · Physics 2016-03-09 Christopher Ferrie , Robin Blume-Kohout

Accurate platform localization is an integral component of most robotic systems. As these robotic systems become more ubiquitous, it is necessary to develop robust state estimation algorithms that are able to withstand novel and…

Robotics · Computer Science 2019-10-15 Ryan M. Watson , Jason N. Gross , Clark N. Taylor , Robert C. Leishman
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