English
Related papers

Related papers: A positive operator-valued measure for two-photon …

200 papers

The temporal response of single-photon detectors is usually obtained by measuring their impulse response to short-pulsed laser sources. In this work, we present an alternative approach using time-correlated photon pairs generated in…

Quantum Physics · Physics 2021-01-25 Lijiong Shen , Jianwei Lee , Antony Winata Hartanto , Pengkian Tan , Christian Kurtsiefer

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

The process of cavity mode quantum state photodetection subject to a nonideal measurement device is under consideration. A set of nonorthogonal probabilistic operator valued measures (POVMs) describing the photodetection process is…

Quantum Physics · Physics 2012-10-18 Alexander Trifanov , George Miroshnichenko

We propose an optical parametric down conversion (PDC) scheme that does not suffer a trade-off between the state-purity of single-photon wave-packets and the rate of packet production. This is accomplished by modifying the PDC process by…

Quantum Physics · Physics 2009-11-11 M. G. Raymer , Jaewoo Noh , K. Banaszek , I. A. Walmsley

We describe a technique for self consistently characterizing both the quantum state of a single qubit system, and the positive-operator-valued measure (POVM) that describes measurements on the system. The method works with only ten…

Quantum Physics · Physics 2021-07-28 A. Stephens , J. M. Cutshall , T. McPhee , M. Beck

We propose a method for characterizing a photodetector by directly reconstructing the Wigner functions of the detector's Positive-Operator-Value-Measure (POVM) elements. This method extends the works of S. Wallentowitz and Vogel [Phys. Rev.…

Quantum Physics · Physics 2019-09-25 Rajveer Nehra , Kevin Valson Jacob

Using the zero time-delay second-order correlation function for studying the photon statistics, we investigate how the photon statistics of the field-modes generated by parametric down-conversion (PDC) process depends on the photon…

Quantum Physics · Physics 2020-08-26 Nilakantha Meher , Anand K. Jha

In this paper we provide a consistent framework to address the notorious decomposition of the single-photon total angular momentum (TAM) into a spin (SAM) and an orbital (OAM) component. In particular, we find that the canonical SAM and…

Quantum Physics · Physics 2018-12-19 Mario Motta , Giacomo Guarnieri , Ludovico Lanz , Beatrix Hiesmayr

A new method for generating entangled photons with controllable frequency correlation via spontaneous parametric down-conversion (SPDC) is presented. The method entails initiating counter-propagating SPDC in a single-mode nonlinear…

The photon statistics of Spontaneous Parametric Down Conversion (SPDC) exhibit dependencies on wavelength, pump power, and coincidence time. Notably, the average photon numbers were found to asymmetrically increase with increasing pump…

Quantum Physics · Physics 2026-05-01 Jeffrey Carvalho , Chiran Wijesundara , Tim Thomay

A quantum measurement, often referred to as positive operator-valued measurement (POVM), is a set of positive operators $P_j=P_j^\dag\geq 0$ summing to identity, $\sum_jP_j=\mathbb{1}$. This can be seen as a generalization of a probability…

Quantum Physics · Physics 2024-12-30 Albert Rico , Karol Życzkowski

We use the Gaussian approximation describing photocount statistics for both the homodyne and the double homodyne (heterodyne) measurements to study asymmetry effects arising from imbalance of the beam splitters and variations in quantum…

Quantum Physics · Physics 2025-12-30 A. S. Naumchik , Roman K. Goncharov , Alexei D. Kiselev

These comments contain two primary improvements to the aforementioned article: Where previously mentioned in passing in section 3.4 of our article, we now provide, using the same basic steps as in Bennink's paper, [Phys. Rev. A 81, 053805…

Quantum Physics · Physics 2025-03-05 James Schneeloch

Spontaneous parametric downconversion (SPDC) has been a key enabling technology in exploring quantum phenomena and their applications for decades. For instance, traditional SPDC, which splits a high energy pump photon into two lower energy…

The spin-coherent-state positive-operator-valued-measure (POVM) is a fundamental measurement in quantum science, with applications including tomography, metrology, teleportation, benchmarking, and measurement of Husimi phase space…

Quantum Physics · Physics 2018-10-03 Ezad Shojaee , Christopher S. Jackson , Carlos A. Riofrio , Amir Kalev , Ivan H. Deutsch

Generalized quantum measurements play a crucial role in quantum mechanics, and symmetric informationally complete positive operator-valued measurements (SIC POVMs) provide a powerful and flexible framework for extracting information from…

This paper proposes a method for estimating and detecting optical signals in practical photon-counting receivers. There are two important aspects of non-perfect photon-counting receivers, namely, (i) dead time which results in blocking…

Signal Processing · Electrical Eng. & Systems 2024-08-21 Chen Wang , Zhiyong Xu , Jingyuan Wang , Jianhua Li , Weifeng Mou , Huatao Zhu , Jiyong Zhao , Yang Su , Yimin Wang , Ailin Qi

In this work we propose and analyse a scheme where the full spatio-temporal correlation of twin photons/beams generated by parametric down-conversion is detected by using its inverse process, i.e. sum frequency generation. Our main result…

The aim of this review paper is to enlighten some recent progresses in quantum optical metrology in the part of quantum efficiency measurements of photo-detectors performed with bi-photon states. The intrinsic correlated nature of entangled…

Quantum Physics · Physics 2015-06-26 G. Brida , M. Genovese , M. Gramegna

The multiphoton states generated by high-gain spontaneous parametric down-conversion (SPDC) in presence of large losses are investigated theoretically and experimentally. The explicit form for the two-photon output state has been found to…