English
Related papers

Related papers: Separable Schmidt modes of a non-separable state

200 papers

Discrete frequency-bin entanglement is an essential resource for applications in quantum information processing. In this Letter, we propose and demonstrate a scheme to generate discrete frequency-bin entanglement with a single piece of…

We measure the transverse entanglement of photon pairs on their propagation from the near to the far field of spontaneous parametric downconversion (SPDC). The Fedorov ratio, depending on the widths of conditional and unconditional…

Quantum Physics · Physics 2015-06-12 Felix Just , Andrea Cavanna , Maria V. Chekhova , Gerd Leuchs

State-of-the-art photon sources based on spontaneous parametric down-conversion (SPDC) currently rely on artificial structuring of the material nonlinearity to satisfy phase-matching conditions. This technique, known as periodic poling, is…

Optics · Physics 2026-04-21 Tim F. Weiss , Hamed Arianfard , Yang Yang , Alberto Peruzzo

We demonstrate how a narrowband pump and a broadband spectrum can be spatially multiplexed by selective coupling them in two distinct modes of a few-mode microstructure fiber. The first mode carries most of the input pump energy, and…

We study the spectral properties of Spontaneous Parametric Down Conversion in a periodically poled waveguided structure of KTP crystal pumped by ultra-short pulses. Our theoretical analysis reveals a strongly multimode and asymmetric…

The ability to entangle distant quantum nodes is essential for the construction of quantum networks and for quantum information processing. For solid-state quantum emitters used as qubits, it can be achieved by photon interference. When the…

Quantum Physics · Physics 2019-10-23 Herbert F Fotso

We propose a dual-pump third-order nonlinear scheme for producing pairs of correlated photons that is less susceptible to Raman noise than typical spontaneous four wave mixing methods (SFWM). Beginning with the full multimode Hamiltonian we…

Quantum Physics · Physics 2016-10-20 Daniel R. Blay , L. G. Helt , M. J. Steel

We present an experimental and theoretical study of photon pairs generated by spontaneous four wave mixing (SFWM), based on birefringent phasematching, in a fiber which supports more than one transverse mode. We present SFWM spectra,…

Configurable and scalable continuous variable quantum networks for measurement-based quantum information protocols or multipartite quantum communication schemes can be obtained via parametric down conversion (PDC) in non-linear waveguides.…

Quantum Physics · Physics 2021-08-17 V. Roman-Rodriguez , B. Brecht , S. Kaali , C. Silberhorn , N. Treps , E. Diamanti , V. Parigi

We performed a second-order spontaneous parametric down-conversion (SPDC) experiment in a Type II phase-matched KTiOPO4 crystal pumped at 532 nm giving birth to a signal beam at 1037 nm and an idler one at 1092 nm along the x-axis of the…

Quantum Physics · Physics 2025-02-10 Julien Bertrand , Véronique Boutou , Benoît Boulanger

We describe a method to detect twin-beam multiphoton entanglement based on a beam splitter and weak nonlinearities. For the twin-beam four-photon entanglement, we explore a symmetry detector. It works not only for collecting two-pair…

Quantum Physics · Physics 2020-08-04 Yingqiu He , Dong Ding , Fengli Yan , Ting Gao

Photonic quantum technologies rely on the efficient generation and interference of indistinguishable photons. Exceptional achievements in this respect have been obtained by domain engineering of quasi-phase-matched parametric…

Implementation of a twin-field quantum key distribution network faces limitations, including the low tolerance of interference errors for phase-matching type protocols and the strict constraint regarding intensity and probability for…

Quantum Physics · Physics 2023-04-11 Yuan-Mei Xie , Chen-Xun Weng , Yu-Shuo Lu , Yao Fu , Yang Wang , Hua-Lei Yin , Zeng-Bing Chen

We propose a spin-orbit strategy for generating dual-wavelength quantum skyrmions, realized either as entangled photon pairs at dual wavelengths or as heralded single-photon states at a given wavelength -- regimes neither previously…

Optimizing the brightness of a spontaneous parametric down conversion (SPDC) source is an important task for many quantum information applications. We investigate the optimal focusing conditions to maximize the number of photons produced in…

Quantum Physics · Physics 2023-09-29 Lorenzo Coccia , Alberto Santamato , Giuseppe Vallone , Paolo Villoresi

We present an ultrabright polarization-entangled photon source that is optimally coupled into single-mode fibers (SMFs). This study theoretically and experimentally examines the characteristics of spontaneous parametric down-conversion…

Quantum Physics · Physics 2024-09-25 Kyungdeuk Park , Jungmo Lee , Dong-Gil Im , Dongkyu Kim , Yong Sup Ihn

Strongly correlated multi-photon states are indispensable resources for advanced quantum technologies, yet their deterministic generation remains challenging due to the inherent weak nonlinearity in most optical systems. Here, we propose a…

Quantum Physics · Physics 2025-11-19 Jia-Qi Li , Anton Frisk Kockum , Xin Wang

Parametric down-conversion (PDC) is the established standard for the practical generation of a multiplicity of quantum optical states. These include two-mode squeezed vacuum, heralded non-Gaussian states and entangled photon pairs. Detailed…

Quantum Physics · Physics 2014-06-18 Malte Avenhaus , Benjamin Brecht , Kaisa Laiho , Christine Silberhorn

We theoretically investigate the spectral entanglement of a multiphoton source generated from the cascade emissions in the cascaded cold atomic ensembles.\ This photon source is highly directional, guaranteed under the four-wave mixing…

Quantum Physics · Physics 2017-04-26 H. H. Jen

Spontaneous symmetry breaking of interacting fermion systems constitutes a major challenge for many-body theory due to the proliferation of new independent scattering channels once absent or degenerate in the symmetric phase. One example is…

Strongly Correlated Electrons · Physics 2025-05-30 Lorenzo Del Re
‹ Prev 1 4 5 6 7 8 10 Next ›