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Related papers: Considerations on the collapse of the wavefunction

200 papers

We study the properties of bi-squeezed tripartite Gaussian states created by two spontaneous parametric down-conversion processes that share a common idler. We give a complete description of the quantum correlations across of all…

Quantum Physics · Physics 2017-06-23 David Edward Bruschi , Carlos Sabín , Gheorghe Sorin Paraoanu

We outline and experimentally demonstrate a method to image pure phase objects using traditional quantum ghost imaging with single pixel detectors. We provide a theoretical description of the process, showing how phase information is…

Quantum Physics · Physics 2022-06-08 Bereneice Sephton , Isaac Nape , Chané Moodley , Jason Francis , Andrew Forbes

Spontaneous parametric down-conversion (SPDC) is a widely used source for photonic entanglement. Years of focused research have led to a solid understanding of the process, but a cohesive analytical description of the paraxial biphoton…

The ghost interference observed for entangled photons is theoretically analyzed using wave-packet dynamics. It is shown that ghost interference is a combined effect of virtual double-slit creation due to entanglement, and quantum erasure of…

Quantum Physics · Physics 2016-08-24 Tabish Qureshi , Pravabati Chingangbam , Sheeba Shafaq

Multi-dimensional entangled states have been proven to be more powerful in some quantum information process. In this paper, down-converted photons from spontaneous parametric down conversion(SPDC) are used to engineer multi-dimensional…

Quantum Physics · Physics 2015-06-26 Xi-Feng Ren , Guo-Ping Guo , Jian Li , Chuan-Feng Li , Guang-Can Guo

The basic strategy underlying models of spontaneous wave function collapse (collapse models) is to modify the Schroedinger equation by including nonlinear stochastic terms, which tend to localize wave functions in space in a dynamical…

Quantum Physics · Physics 2015-06-18 A. Bassi , H. Ulbricht

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…

One-photon and two-photon wavepackets of entangled two-photon states in spontaneous parametric down-conversion (SPDC) fields are calculated and measured experimentally. For type-II SPDC, measured one-photon and two-photon wavepackets agree…

Quantum Physics · Physics 2009-11-10 Yoon-ho Kim

A method for exploring photon-number entangled states with weak nonlinearities is described. We show that it is possible to create and detect such entanglement at various scales, ranging from microscopic to macroscopic systems. In the…

Quantum Physics · Physics 2015-10-28 Yingqiu He , Dong Ding , Fengli Yan , Ting Gao

A transparent polarisation sensitive phase pattern exhibits a position and polarisation dependent phase shift of transmitted light and it represents a unitary transformation. A quantum ghost image of this pattern is produced with…

Quantum Physics · Physics 2023-03-14 Aditya Saxena , Manpreet Kaur , Vipin Devrari , Mandip Singh

Coincidence imaging, also known as ghost imaging, is a technique that exploits correlations between two particles to reconstruct information about a specimen. The particle that relays the spatial information about the object remains…

We present an entanglement-based quantitative phase gradient microscopy technique that employs principles from quantum ghost imaging and ghost diffraction. In this method, a transparent sample is illuminated by both photons of an entangled…

Quantum Physics · Physics 2026-03-09 Yingwen Zhang , Paul-Antoine Moreau , Duncan England , Ebrahim Karimi , Benjamin Sussman

We propose a class of path-entangled photon Fock states for robust quantum optical metrology, imaging, and sensing in the presence of loss. We model propagation loss with beam-splitters and derive a reduced density matrix formalism from…

Quantum Physics · Physics 2009-03-13 Sean D. Huver , Christoph F. Wildfeuer , Jonathan P. Dowling

The statistical properties of photons are fundamental to investigating quantum mechanical phenomena using light. In multi-photon, two-mode systems, correlations may exist between outcomes of measurements made on each mode which exhibit…

Quantum Physics · Physics 2017-02-06 Evan Meyer-Scott , Johannes Tiedau , Georg Harder , Lynden K. Shalm , Tim J. Bartley

In this letter, we have considered an electron in a coupled quantum dot system interacting with a detector represented by a point contact. We present a dynamical model for wave function collapse in the strong coupling to the detector limit.…

Mesoscale and Nanoscale Physics · Physics 2017-11-23 H. Cruz

We present a model to detect a classical state mixed with an idler photon from a polarization-entangled pair. A weak coherent light with a well-defined polarization, matched in wavelength to the idler photon, is injected into the idler…

Quantum Physics · Physics 2026-02-24 Kim Fook Lee , Prem Kumar

We develop and experimentally verify a theory of Type-II spontaneous parametric down-conversion (SPDC) in media with inhomogeneous distributions of second-order nonlinearity. As a special case, we explore interference effects from SPDC…

Two-photon states generated through degenerate spontaneous parametric down-conversion (SPDC) can exhibit sharp correlations in the transverse spatial coordinates. This property leads to unique free-space propagation features. Here, we show…

Quantum Physics · Physics 2025-05-20 Nazanin Dehghan , Alessio D'Errico , Yingwen Zhang , Benjamin Sussman , Ebrahim Karimi

A quantum system composed of two or more subsystems can be in an entangled state, i.e. a state in which the properties of the global system are well defined but the properties of each subsystem are not. Entanglement is at the heart of…

The two-mode even and odd coherent states and two-mode squeezed correlated state are discussed. Photon distribution functions, means, dispersions, Fano factor for even and odd coherent states and squeezed correlated state are calculated.…

Quantum Physics · Physics 2019-03-27 Sergey V. Kuznetsov , Aleksander V. Kyusev , Olga V. Man'ko