English
Related papers

Related papers: Pointer-based simultaneous measurements of conjuga…

200 papers

We consider the apparatus in a quantum measurement process to be in a mixed state. We propose a simple upper bound on the probability of correctly distinguishing any number of mixed states. We use this to derive fundamental bounds on the…

Quantum Physics · Physics 2007-05-23 S. Bose , V. Vedral

We investigate how the concepts of optimal control of measurables of a system with a time dependent Hamiltonian may be mixed with the level set technique to keep the desired entity invariant. We derive sets of equations for this purpose and…

Quantum Physics · Physics 2007-05-23 Fariel Shafee

It has recently been shown that finding the optimal measurement on the environment for stationary Linear Quadratic Gaussian control problems is a semi-definite program. We apply this technique to the control of the EPR-correlations between…

Quantum Physics · Physics 2009-11-13 Stefano Mancini , Howard M. Wiseman

We present a phenomenological reduced-order model to capture the transition to thermoacoustic instability in turbulent combustors. The model is based on the framework of synchronization and considers the acoustic field and the unsteady heat…

Adaptation and Self-Organizing Systems · Physics 2022-06-14 Yue Weng , Vishnu R. Unni , R. I. Sujith , Abhishek Saha

The major problem of multiparameter quantum estimation theory is to find an ultimate measurement scheme to go beyond the standard quantum limits that each quasi-classical estimation measurement is limited by. Although, in some specifics…

Quantum Physics · Physics 2022-03-21 Bakmou Lahcen , Daoud Mohammed

The recently established universal uncertainty principle revealed that two nowhere commuting observables can be measured simultaneously in some state, whereas they have no joint probability distribution in any state. Thus, one measuring…

Quantum Physics · Physics 2011-06-24 Masanao Ozawa

Chained correlation inequalities involving pairwise correlations of qubit observables in the equatorial plane are constructed based on the positivity of a sequence of moment matrices. When a jointly measurable set of fuzzy POVMs is employed…

Quantum Physics · Physics 2017-05-17 H. S. Karthik , A. R. Usha Devi , J. Prabhu Tej , A. K. Rajagopal , Sudha , A. Narayanan

We solve the model of N quantum Brownian oscillators linearly coupled to an environment of quantum oscillators at finite temperature, with no extra assumptions about the structure of the system-environment coupling. Using a compact…

Quantum Physics · Physics 2011-06-29 C. H. Fleming , Albert Roura , B. L. Hu

Quantum mechanics predicts the joint probability distribution of the outcomes of simultaneous measurements of commuting observables, but, in the state of the art, has lacked the operational definition of simultaneous measurements. The…

Quantum Physics · Physics 2009-10-31 Masanao Ozawa

The quantum measurement problem is revisited and discussed in terms of a new solvable measurement model which basic ingredient is the quantum model of a controlled single-bit memory. The structure of this model involving strongly coupled…

Quantum Physics · Physics 2013-05-22 Robert Alicki

A model of an electrical point contact coupled to a mechanical system (oscillator) is studied to simulate the dephasing effect of measurement on a quantum system. The problem is solved at zero temperature under conditions of strong…

Condensed Matter · Physics 2015-06-24 D. Mozyrsky , I. Martin

Measurement incompatibility is one of the cornerstones of quantum theory. This phenomenon appears in many forms, of which the concept of non-joint measurability has received considerable attention in the recent years. In order to…

Quantum Physics · Physics 2023-04-05 Juha-Pekka Pellonpää , Sébastien Designolle , Roope Uola

We consider the usage of dynamical decoupling in quantum metrology, where the joint evolution of system plus environment is described by a Hamiltonian. We demonstrate that by ultra-fast unitary control operations acting locally only on…

Quantum Physics · Physics 2016-08-03 P. Sekatski , M. Skotiniotis , W. Dür

Quantum metrology promises precision beyond classical limits, yet environmental noise typically degrades the quantum resources required for such enhancement. In this work, we investigate frequency estimation in noisy continuous-variable…

Quantum Physics · Physics 2026-05-08 Ayan Patra , Manju , Aditi Sen De , Matteo G. A. Paris

The measurement outcomes of two incompatible observables on a particle can be precisely predicted when it is maximally entangled with a quantum memory, as quantified recently [Nature Phys. 6, 659 (2010)]. We explore the behavior of the…

Quantum Physics · Physics 2012-07-26 Z. Y. Xu , W. L. Yang , M. Feng

Projective measurement is a commonly used assumption in quantum mechanics. However, advances in quantum measurement techniques allow for partial measurements, which accurately estimate state information while keeping the wavefunction…

Quantum Physics · Physics 2021-08-24 Jonathan Monroe

We introduce a new information-theoretic formulation of quantum measurement uncertainty relations, based on the notion of relative entropy between measurement probabilities. In the case of a finite-dimensional system and for any approximate…

Mathematical Physics · Physics 2018-03-02 Alberto Barchielli , Matteo Gregoratti , Alessandro Toigo

In quantum mechanics, joint measurements of non-commuting observables are only possible if a minimal unavoidable measurement uncertainty is accepted. On the other hand, correlations between non-commuting observables can exceed classical…

Quantum Physics · Physics 2019-07-24 Holger F. Hofmann

We discuss a balanced homodyne detection scheme with imperfect detectors in the framework of the operational approach to quantum measurement. We show that a realistic homodyne measurement is described by a family of operational observables…

atom-ph · Physics 2009-10-28 Konrad Banaszek , Krzysztof Wodkiewicz

We propose a class of incompatibility measures for quantum observables based on quantifying the effect of a measurement of one observable on the statistics of the outcomes of another. Specifically, for a pair of observables $A$ and $B$ with…

Quantum Physics · Physics 2014-09-30 Prabha Mandayam , M. D. Srinivas