English
Related papers

Related papers: Single-Mode Parametric-Down-Conversion States with…

200 papers

Coincidence-count discrimination have turned utterly practical in the characterization of photon-pair processes and heralded single photons. Here, we implement a heralded single photon source based on parametric down-conversion (PDC) in a…

Quantum Physics · Physics 2025-12-22 Daniel Borrero Landazabal , Kaisa Laiho

Entanglement of high dimensional states is becoming increasingly important for quantum communication and computing. The most common source of entangled photons is spontaneous parametric down conversion (SPDC), where the degree of frequency…

Quantum Physics · Physics 2020-01-22 C. Okoth , E. Kovlakov , F. Boensel , A. Cavanna , S. Straupe , S. P. Kulik , M. V. Chekhova

Path-entangled multi-photon states allow optical phase-sensing beyond the shot-noise limit, provided that an efficient parity measurement can be implemented. Realising this experimentally is technologically demanding, as it requires…

Here, we present a proof-of-principle high-dimensional quantum key distribution (QKD) protocol utilizing the position and momentum entanglement of photon pairs. The protocol exploits the fact that position and momentum form mutually…

Quantum Physics · Physics 2026-03-09 Lukas Scarfe , Yingwen Zhang , Ebrahim Karimi

A detailed theoretical analysis of the spatiotemporal mode of a single photon prepared via conditional measurements on a photon pair generated in the process of parametric down-conversion is presented. The maximum efficiency of coupling the…

Quantum Physics · Physics 2009-11-07 T. Aichele , A. I. Lvovsky , S. Schiller

We experimentally demonstrate the generation of multi-photon Fock states with up to three photons in well-defined spatial-temporal modes synchronized with a classical clock. The states are characterized using quantum optical homodyne…

Quantum Physics · Physics 2013-02-27 Merlin Cooper , Laura J. Wright , Christoph Söller , Brian J. Smith

We present a method to reconstruct the complete statistical mode structure and optical losses of multimode conjugated optical fields using an experimentally measured joint photon-number probability distribution. We demonstrate that this…

The widespread availability of quantum entanglement with photons, in the guise of two-mode squeezed states, can be attributed to the phenomenon of parametric down-conversion. A reinterpretation of this effect with macroscopic mechanical…

Mesoscale and Nanoscale Physics · Physics 2014-10-21 I. Mahboob , H. Okamoto , K. Onomitsu , H. Yamaguchi

Developing a quantum light source that carries more than one bit per photon is pivotal for expanding quantum information applications. Characterizing a high-dimensional multiple-degree-of-freedom source at the single-photon level is…

Quantum Physics · Physics 2025-05-09 Dong Beom Kim , Xiye Hu , Alfred B. U'Ren , Karina Garay-Palmett , Virginia O. Lorenz

While experimental measurements of photon correlations have become routine in laboratories, theoretical access to these quantities for the light generated in complex nanophotonic devices remains a major challenge. Current methods are…

In this work we study the first step in photosynthesis for the limiting case of a single photon interacting with photosystem II (PSII). We model our system using quantum trajectory theory, which allows us to consider not only the average…

Biological Physics · Physics 2022-08-10 Robert L. Cook , Liwen Ko , K. Birgitta Whaley

The complete measurement of the quantum state of two correlated photons requires reconstructing the amplitude and phase of the biphoton wavefunction. We show how, by means of spatially resolved single photon detection, one can infer the…

Quantum Physics · Physics 2025-06-26 Nazanin Dehghan , Alessio D'Errico , Francesco Di Colandrea , Ebrahim Karimi

Broadband light sources play essential roles in diverse fields, such as high-capacity optical communications, optical coherence tomography, optical spectroscopy, and spectrograph calibration. Though an ultrabroadband nonclassical state from…

Two-photon time-frequency entanglement is a valuable resource in quantum information. Resolving the wavepacket of ultrashort pulsed single-photons, however, is a challenge. Here, we demonstrate remote spectral shaping of single photon…

Quantum Physics · Physics 2020-10-21 Vahid Ansari , John M. Donohue , Benjamin Brecht , Christine Silberhorn

We report the implementation of a high-rate source of single and two-photon states. By combining the advantages of short pulses and cavities, heralding rates up to 250kHz with 88% fidelity have been obtained for the single photons as well…

Gaussian states are ubiquitous in quantum optics and information processing, and it is essential to have effective tools for their characterization. One such tool is a photon-number-resolving detector, and the simplest configuration…

Quantum Physics · Physics 2025-12-12 Arik Avagyan , Emanuel Knill , Scott Glancy

Using a continuous-wave type-II optical parametric oscillator below threshold, we have demonstrated a novel source of heralded single-photons with high-fidelity. The generated state is characterized by homodyne detection and exhibits a 79%…

Quantum Physics · Physics 2012-10-11 Olivier Morin , Virginia D'Auria , Claude Fabre , Julien Laurat

We have built a quantum light source capable of producing different types of quantum states. The quantum light source is based on entangled state preparation in the process of spontaneous parametric down-conversion. The single-photon…

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…

It is shown that parametric downconversion, with a short-duration pump pulse and a long nonlinear crystal that is appropriately phase matched, can produce a frequency-entangled biphoton state whose individual photons are coincident in…

Quantum Physics · Physics 2009-11-07 Vittorio Giovannetti , Lorenzo Maccone , Jeffrey H. Shapiro , Franco N. C. Wong