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Related papers: State reconstruction by on/off measurements

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Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, also an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction…

The characterization of quantum features in large Hilbert spaces is a crucial requirement for testing quantum protocols. In the continuous variables encoding, quantum homodyne tomography requires an amount of measurements that increases…

Quantum Physics · Physics 2020-10-29 Valeria Cimini , Marco Barbieri , Nicolas Treps , Mattia Walschaers , Valentina Parigi

We introduce a scheme to reconstruct an arbitrary quantum state of a mechanical oscillator network. We assume that a single element of the network is coupled to a cavity field via a linearized optomechanical interaction, whose time…

Quantum Physics · Physics 2016-11-08 Darren W. Moore , Tommaso Tufarelli , Mauro Paternostro , Alessandro Ferraro

An analysis of the homodyne tomography process that is often used to determine the Wigner functions of quantum optical states is performed to consider the effects of the spatiotemporal degrees of freedom. The homodyne tomography process…

Quantum Physics · Physics 2022-08-31 Filippus S. Roux

New algorithm for quantum state estimation based on the maximum likelihood estimation is proposed. Existing techniques for state reconstruction based on the inversion of measured data are shown to be overestimated since they do not…

Quantum Physics · Physics 2009-10-30 Zdenek Hradil

Reconstructing the state of a complex quantum system represents a pivotal task for all quantum information applications, both for characterization purposes and for verification of quantum protocols. Recent technological developments have…

Quantum tomography is a crucial tool for characterizing quantum states and devices and estimating nonlinear properties of the systems. Performing full quantum state tomography on an $N_\mathrm{q}$ qubit system requires an exponentially…

Quantum Physics · Physics 2025-09-09 Zhixin Song , Hang Ren , Melody Lee , Bryan Gard , Nicolas Renaud , Spencer H. Bryngelson

The image reconstruction of partially coherent light is interpreted as the quantum state reconstruction. The efficient method based on maximum-likelihood estimation is proposed to acquire information from registered intensity measurements…

Optics · Physics 2011-07-22 M. Jezek , Z. Hradil

Due to the exponential complexity of the resources required by quantum state tomography (QST), people are interested in approaches towards identifying quantum states which require less effort and time. In this paper, we provide a tailored…

Information Theory · Computer Science 2017-08-02 K. Li , J. Zhang , S. Cong

Single-photon avalanche detectors (SPADs) are crucial sensors of light for many fields and applications. However, they are not able to resolve photon number, so typically more complex and more expensive experimental setups or devices must…

Quantum Physics · Physics 2024-04-15 Patrick Banner , Deniz Kurdak , Yaxin Li , Alan Migdall , J. V. Porto , S. L. Rolston

We formulate necessary and sufficient conditions for a symplectic tomogram of a quantum state to determine the density state. We establish a connection between the (re)construction by means of symplectic tomograms with the construction by…

Quantum Physics · Physics 2010-05-25 A. Ibort , V. I. Man'ko , G. Marmo , A. Simoni , F. Ventriglia

In the field of continuous-variable quantum information processing, non-Gaussian states with negative values of the Wigner function are crucial for the development of a fault-tolerant universal quantum computer. While several non-Gaussian…

We significantly extend recently developed methods to faithfully reconstruct unknown quantum states that are approximately low-rank, using only a few measurement settings. Our new method is general enough to allow for measurements from a…

Quantum Physics · Physics 2012-07-11 Matthias Ohliger , Vincent Nesme , David Gross , Yi-Kai Liu , Jens Eisert

We demonstrate a novel experimental technique for quantum-state tomography of the collective density matrix. It is based on measurements of the polarization of light, traversing the atomic vapor. To assess the technique's robustness against…

Quantum Physics · Physics 2025-08-29 Marek Kopciuch , Magdalena Smolis , Adam Miranowicz , Szymon Pustelny

In quantum optics, the quantum state of a light beam is represented through the Wigner function, a density on $\mathbb R^2$ which may take negative values but must respect intrinsic positivity constraints imposed by quantum physics. In the…

Statistics Theory · Mathematics 2015-06-24 Karim Lounici , Katia Meziani , Gabriel Peyré

We propose an efficient quantum state tomography method inspired by compressed sensing and threshold quantum state tomography that can drastically reduce the number of measurement settings to reconstruct the density matrix of an $N$-qudit…

Quantum Physics · Physics 2025-04-01 Giovanni Garberoglio , Maurizio Dapor , Diego Maragnano , Marco Liscidini , Daniele Binosi

In this article, we introduce a framework for quantum state tomography of qutrits by projective measurements. The framework is based on photon-counting with measurement results distorted due to the Poisson noise and dark counts. Two…

Quantum Physics · Physics 2021-10-26 Jakub Szlachetka , Artur Czerwinski

An experiment is performed to reconstruct an unknown photonic quantum state with a limited amount of copies. A semi-quantum reinforcement learning approach is employed to adapt one qubit state, an "agent," to an unknown quantum state, an…

The need to retain the relative phases in quantum mechanics implies an addition law parametrized by a phase of two density operators required for the purification of a density matrix. This is shown with quantum tomography and the Wigner…

Quantum Physics · Physics 2007-05-23 V. I. Man'ko , G. Marmo , E. C. G. Sudarshan , F. Zaccaria

Quantum information protocols often rely on tomographic techniques to determine the state of the system. A popular method of encoding information is on the different paths a photon may take, for example, parallel waveguides in integrated…

Quantum Physics · Physics 2019-06-11 Davor Curic , Lambert Giner , Jeff S. Lundeen