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Related papers: Filter functions for the Glauber-Sudarshan $P$-fun…

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We experimentally examine the nonclassical character of a class of non-Gaussian states known as phase-diffused squeezed states. These states may show no squeezing effect at all, and therefore provide an interesting example to test…

Quantum Physics · Physics 2013-05-29 T. Kiesel , W. Vogel , B. Hage , J. DiGuglielmo , A. Samblowski , R. Schnabel

In a recent paper [Phys.~Rev.~A {\bf 91}, 053844 (2015)], Mukamel and Dorfman compare spectroscopies performed with classical vs.~quantum light, and conclude that \textit{nonlinear} quantum-spectroscopy signals cannot be obtained from…

Mesoscale and Nanoscale Physics · Physics 2015-07-08 M. Kira , S. W. Koch , S. T. Cundiff

When applied to different input states, an imperfect quantum operation yields output states with varying fidelities, defined as the absolute square of their overlap with the desired states. We present an expression for the distribution of…

Quantum Physics · Physics 2009-02-26 Line Hjortshoj Pedersen , Niels Martin Moller , Klaus Molmer

We demonstrate that the task of determining an unknown quantum state can be accomplished efficiently by making a sequential measurement of two observables $\hat{A}$ and $\hat{B}$, provided that the two observables are chosen in such a way…

Quantum Physics · Physics 2013-10-22 Antonio Di Lorenzo

Noisy teleportation of nonclassical quantum states via a two-mode squeezed-vacuum state is studied with the completely positive map and the Glauber-Sudarshan $P$-function. Using the nonclassical depth as a measure of transmission…

Quantum Physics · Physics 2009-11-07 Masahiro Takeoka , Masashi Ban , Masahide Sasaki

An extension of the Born rule, the {\it quantum typicality rule}, has recently been proposed [B. Galvan: Found. Phys. 37, 1540-1562 (2007)]. Roughly speaking, this rule states that if the wave function of a particle is split into…

Quantum Physics · Physics 2008-06-08 Bruno Galvan

We study the task of lifting arbitrary quantum states and channels to purifications and Stinespring dilations, respectively, in both the probabilistic exact and deterministic approximate settings. We formalize this task through a general…

Quantum Physics · Physics 2026-05-08 Zoe G. del Toro , Jessica Bavaresco

In this paper, we consider the generalized measurement where one particular quantum signal is unambiguously extracted from a set of non-commutative quantum signals and the other signals are filtered out. Simple expressions for the maximum…

Quantum Physics · Physics 2009-11-10 Masahiro Takeoka , Masashi Ban , Masahide Sasaki

We study the problem of optimal estimation and control of linear systems using quantized measurements, with a focus on applications over sensor networks. We show that the state conditioned on a causal quantization of the measurements can be…

Information Theory · Computer Science 2015-03-13 Ravi Teja Sukhavasi , Babak Hassibi

A strong limitation of linear optical quantum computing is the probabilistic operation of two-quantum bit gates based on the coalescence of indistinguishable photons. A route to deterministic operation is to exploit the single-photon…

Efficient measures to determine similarity of quantum states, such as the fidelity metric, have been widely studied. In this paper, we address the problem of defining a similarity measure for quantum operations that can be…

Quantum Physics · Physics 2022-11-23 Yiyou Chen , Hideyuki Miyahara , Louis-S. Bouchard , Vwani Roychowdhury

This paper delves into the significance of the tomographic probability density function (pdf) representation of quantum states, shedding light on the special classes of pdfs that can be tomograms. Instead of using wave functions or density…

Quantum Physics · Physics 2024-01-23 L. A. Markovich , J. Urbanetz , V. I. Man'ko

We consider realistic measurement systems, where measurements are accompanied by decoherence processes. The aim of this work is the construction of methods and algorithms for precise quantum measurements with fidelity close to the…

Quantum Physics · Physics 2017-01-10 Yu. I. Bogdanov , B. I. Bantysh , N. A. Bogdanova , A. B. Kvasnyy , V. F. Lukichev

Quantum state tomography is a central technique for the characterization and verification of quantum systems. Standard tomography is widely used for low-dimensional systems, but for larger systems, it becomes impractical due to the…

We describe an optimized, self-correcting procedure for the Bayesian inference of pure quantum states. By analyzing the history of measurement outcomes at each step, the procedure returns the most likely pure state, as well as the optimal…

Quantum Physics · Physics 2015-09-14 Amir Kalev , Itay Hen

Quantum state discrimination is a fundamental concept in quantum information theory, which refers to a class of techniques to identify a specific quantum state through a positive operator-valued measure. In this work, we investigate how…

Quantum Physics · Physics 2025-07-09 Hyunho Cha , Jungwoo Lee

Polarization quasiprobability distribution defined in the Stokes space shares many important properties with the Wigner function for the position and momentum. Most notably, they both give correct one-dimensional marginal probability…

Quantum Physics · Physics 2017-08-16 K. Yu. Spasibko , M. V. Chekhova , F. Ya. Khalili

Quantum state smoothing is a technique for estimating the quantum state of a partially observed quantum system at time $\tau$, conditioned on an entire observed measurement record (both before and after $\tau$). However, this smoothing…

Quantum Physics · Physics 2020-04-14 Kiarn T. Laverick , Areeya Chantasri , Howard M. Wiseman

Several finite dimensional quasi-probability representations of quantum states have been proposed to study various problems in quantum information theory and quantum foundations. These representations are often defined only on restricted…

Quantum Physics · Physics 2008-08-07 Christopher Ferrie , Joseph Emerson

We consider the Wigner quasi-probability distribution function of a single mode of an electromagnetic or matter-wave field to address the question of whether a direct stochastic sampling and binning of the absolute square of the complex…

Quantum Physics · Physics 2016-09-13 R. J. Lewis-Swan , M. K. Olsen , K. V. Kheruntsyan