English
Related papers

Related papers: Characterizing quantum detectors by Wigner functio…

200 papers

Improved measurement techniques are central to technological development and foundational scientific exploration. Quantum optics relies upon detectors sensitive to non-classical features of light, enabling precise tests of physical laws and…

Quantum Physics · Physics 2014-07-18 Merlin Cooper , Michal Karpinski , Brian J. Smith

We propose strongly consistent algorithms for reconstructing the characteristic function 1_K of an unknown convex body K in R^n from possibly noisy measurements of the modulus of its Fourier transform \hat{1_K}. This represents a complete…

Metric Geometry · Mathematics 2016-05-02 Gabriele Bianchi , Richard J. Gardner , Markus Kiderlen

Time-domain balanced homodyne detection is performed on two well-separated temporal modes sharing a single photon. The reconstructed density matrix of the two-mode system is used to prove and quantify its entangled nature, while the Wigner…

Quantum Physics · Physics 2009-11-13 Milena D'Angelo , Alessandro Zavatta , Valentina Parigi , Marco Bellini

Detectors that can resolve photon number are needed in many quantum information technologies. In order to be useful in quantum information processing, such detectors should be simple, easy to use, and be scalable to resolve any number of…

Using tomographic reconstruction we determine the complete internuclear quantum state, represented by the Wigner function, of a dissociating I2 molecule based on femtosecond time resolved position and momentum distributions of the atomic…

Quantum Physics · Physics 2009-11-10 Esben Skovsen , Henrik Stapelfeldt , Soren Juhl , Klaus Molmer

We present the reconstruction of the Wigner function of some classical pulsed optical states obtained by direct measurement of the detected-photon probability distributions of the state displaced by a coherent field. We use a photodetector…

Quantum Physics · Physics 2015-05-13 Maria Bondani , Alessia Allevi , Alessandra Andreoni

Particle sensing in optical tweezers systems provides information on the position, velocity and force of the specimen particles. The conventional quadrant detection scheme is applied ubiquitously in optical tweezers experiments to quantify…

Quantum Physics · Physics 2010-07-07 Jian Wei Tay , Magnus T. L. Hsu , Warwick P. Bowen

We propose a technique for performing quantum state tomography of photonic polarization-encoded multi-qubit states. Our method uses a single rotating wave plate, a polarizing beam splitter and two photon-counting detectors per photon mode.…

Quantum Physics · Physics 2013-01-18 Mohammadreza Mohammadi , Agata M. Branczyk , Daniel F. V. James

An experimental demonstration of two-qutrit state tomography via one-qutrit symmetric informationally complete positive operator-valued measure (SIC-POVM) is presented. A two-qutrit state is encoded in the transversal paths of a spontaneous…

Quantum Physics · Physics 2013-12-05 W. M. Pimenta , B. Marques , T. O. Maciel , R. O. Vianna , A. Delgado , C. Saavedra , S. Pádua

Photon number resolving detectors can enhance the performance of many practical quantum cryptographic setups. In this paper, we employ a simple method to estimate the statistics provided by such a photon number resolving detector using only…

Quantum Physics · Physics 2015-05-13 Tobias Moroder , Marcos Curty , Norbert Lütkenhaus

Photodetection plays a key role in basic science and technology, with exquisite performance having been achieved down to the single photon level. Further improvements in photodetectors would open new possibilities across a broad range of…

Quantum Physics · Physics 2019-01-30 Steve M. Young , Mohan Sarovar , François Léonard

We directly sample the exponential moments of the canonical phase for various quantum states from the homodyne output. The method enables us to study the phase properties experimentally, without making the detour via reconstructing the…

Quantum Physics · Physics 2007-05-23 M. Dakna , G. Breitenbach , J. Mlynek , T. Opatrny , S. Schiller , D. -G. Welsch

A pulsed balanced homodyne detector has been developed for precise measurements of electric field quadratures of pulsed optical quantum states. A high level of common mode suppression (> 85 dB) and low electronic noise (730 electrons per…

Quantum Physics · Physics 2009-11-07 H. Hansen , T. Aichele , C. Hettich , P. Lodahl , A. I. Lvovsky , J. Mlynek , S. Schiller

The interaction of a quantum system with the environment leads to the so-called quantum decoherence. Beyond its fundamental significance, the understanding and the possible control of this dynamics in various scenarios is a key element for…

Quantum Physics · Physics 2011-09-05 Virginia D'Auria , Noriyuki Lee , Taoufik Amri , Claude Fabre , Julien Laurat

Homodyne detection is a phase-sensitive measurement technique, essential for the characterization of continuous-variable (CV)-encoded quantum states of light. It is a key component to the implementation of CV quantum-information protocols…

We present a comprehensive theory and an easy to follow method for the design and construction of a wideband homodyne detector for time-domain quantum measurements. We show how one can evaluate the performance of a detector in a specific…

Instrumentation and Detectors · Physics 2015-06-03 Ranjeet Kumar , Erick Barrios , Andrew MacRae , E. Cairns , E. H. Huntington , A. I. Lvovsky

We present the results of the first photonic implementation of a new method for quantum process tomography. The method (originally presented by A. Bendersky et al, Phys. Rev. Lett 100, 190403 (2008)) enables the estimation of any element of…

Quantum Physics · Physics 2010-02-25 Christian Tomás Schmiegelow , Miguel Antonio Larotonda , Juan Pablo Paz

This dissertation serves as a general introduction to Wigner functions, phase space, and quantum metrology but also strives to be useful as a how-to guide for those who wish to delve into the realm of using continuous variables, to describe…

Quantum Physics · Physics 2016-05-05 Bryan Gard

Photo-detection plays a fundamental role in experimental quantum optics and is of particular importance in the emerging field of linear optics quantum computing. Present theoretical treatment of photo-detectors is highly idealized and fails…

Quantum Physics · Physics 2009-11-11 Peter P. Rohde , Timothy C. Ralph

Gaussian bipartite states are basic tools for the realization of quantum information protocols with continuous variables. Their complete characterization is obtained by the reconstruction of the corresponding covariance matrix. Here we…

Quantum Physics · Physics 2016-04-27 D. Buono , G. Nocerino , V. D'Auria , A. Porzio , S. Olivares , M. G. A. Paris