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Related papers: Coherent quantum tomography

200 papers

Using a new Bayesian method for solving inverse quantum problems, potentials of quantum systems are reconstructed from coordinate measurements in non-stationary states. The approach is based on two basic inputs: 1. a likelihood model,…

Quantum Physics · Physics 2007-05-23 J. C. Lemm

Quantum measurements affect the state of the observed systems via back-action. While projective measurements extract maximal classical information, they drastically alter the system's configuration. In contrast, indirect measurements…

Quantum Physics · Physics 2026-04-06 Giacomo Franceschetto , Marcin Płodzień , Maciej Lewenstein , Antonio Acín , Pere Mujal

Computational time reversal imaging can be used to locate the position of multiple scatterers in a known background medium. The current methods for computational time reversal imaging are based on the null subspace projection operator,…

Data Analysis, Statistics and Probability · Physics 2009-06-16 M. Andrecut

We present a method for quantum state tomography that enables the efficient estimation, with fixed precision, of any of the matrix elements of the density matrix of a state, provided that the states from the basis in which the matrix is…

Quantum Physics · Physics 2015-06-12 Ariel Bendersky , Juan Pablo Paz

Quantum state tomography is an essential component of modern quantum technology. In application to continuous-variable harmonic-oscilator systems, such as the electromagnetic field, existing tomography methods typically reconstruct the…

Quantum Physics · Physics 2023-01-09 Ekaterina Fedotova , Nikolai Kuznetsov , Egor Tiunov , A. E. Ulanov , A. I. Lvovsky

We show that any unitary transformation performed on the quantum state of a closed quantum system, describes an inner, reversible, generalized quantum measurement. We also show that under some specific conditions it is possible to perform a…

Quantum Physics · Physics 2009-11-11 Paola Zizzi

We show that measurement can recover the quantum coherence of a qubit in a non-Markovian environment. The experimental demonstration in an optical system is provided by comparing the visibilities (and fidelities) of the final states with…

Quantum Physics · Physics 2009-11-13 JinShi Xu , ChuanFeng Li , Ming Gong , XuBo Zou , Lei Chen , Geng Chen , JianShun Tang , GuangCan Guo

The measurement of a quantum system becomes itself a quantum-mechanical process once the apparatus is internalized. That shift of perspective may result in different physical predictions for a variety of reasons. We present a model…

Mathematical Physics · Physics 2019-08-28 Martin Fraas , Gian Michele Graf , Lisa Hänggli

We consider the quantum dynamics of a test particle in noncommutative space under the influence of linearized gravitational waves in the long wave-length and low-velocity limit. A prescription for quantizing the classical Hamiltonian for…

High Energy Physics - Theory · Physics 2009-11-18 Anirban Saha , Sunandan Gangopadhyay

In quantum computing, the indirect measurement of unitary operators such as the Hadamard test plays a significant role in many algorithms. However, in certain cases, the indirect measurement can be reduced to the direct measurement, where a…

Quantum Physics · Physics 2019-08-14 Kosuke Mitarai , Keisuke Fujii

Quantum mechanics dictates that a continuous measurement of the position of an object imposes a random back action perturbation on its momentum. This randomness translates with time into position uncertainty, thus leading to the well known…

We introduce the concept of quantum weight as a fundamental property of insulating states of matter that is encoded in the ground-state static structure and measures quantum fluctuation in electrons' center of mass. We find a sum rule that…

Strongly Correlated Electrons · Physics 2024-01-26 Yugo Onishi , Liang Fu

The problem of reconstructing information on a physical system from data acquired in long sequences of direct (projective) measurements of some simple physical quantities - histories - is analyzed within quantum mechanics; that is, the…

Mathematical Physics · Physics 2016-11-24 M. Ballesteros , M. Fraas , J. Fröhlich , B. Schubnel

Quantum operations describe any state change allowed in quantum mechanics, including the evolution of an open system or the state change due to a measurement. In this letter we present a general method based on quantum tomography for…

Quantum Physics · Physics 2009-11-06 G. M. D'Ariano , P. Lo Presti

We propose a technique to obtain sub-wavelength resolution in quantum imaging with potentially 100% contrast using incoherent light. Our method requires neither path-entangled number states nor multi-photon absorption. The scheme makes use…

Quantum Physics · Physics 2009-11-13 C. Thiel , T. Bastin , J. Martin , E. Solano , J. von Zanthier , G. S. Agarwal

The time-symmetric formalism endows the weak measurement and its outcome, the weak value,many unique features. In particular, it allows a direct tomography of quantum states without resort to complicated reconstruction algorithms and…

Quantum Physics · Physics 2021-11-01 Liang Xu , Huichao Xu , Tao Jiang , Feixiang Xu , Kaimin Zheng , Ben Wang , Aonan Zhang , Lijian Zhang

We propose a method -- a quantum time mirror (QTM) -- for simulating a partial time-reversal of the free-space motion of a nonrelativistic quantum wave packet. The method is based on a short-time spatially-homogeneous perturbation to the…

Quantum Physics · Physics 2018-05-28 Phillipp Reck , Cosimo Gorini , Arseni Goussev , Viktor Krueckl , Mathias Fink , Klaus Richter

Quantum state tomography--the practice of estimating a quantum state by performing measurements on it--is useful in a variety of contexts. We introduce "gentle tomography" as a version of tomography that preserves the measured quantum data.…

Quantum Physics · Physics 2007-05-23 Charles H. Bennett , Aram W. Harrow , Seth Lloyd

This paper proposes an intrinsic or background-independent quantum framework based on entangled state rather than absolute quantum state, it describes a quantum relative state between the under-study quantum system and the quantum measuring…

Quantum Physics · Physics 2026-03-13 M. J. Luo

In this article, we consider the inverse problem of determining spatially heterogeneous absorption and diffusion coefficients from a single measurement of the absorbed energy (in the steady-state diffusion approximation of light transfer).…

Analysis of PDEs · Mathematics 2015-10-09 Elena Beretta , Monika Muszkieta , Wolf Naetar , Otmar Scherzer