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Related papers: Partial coherence and coherence length in StimPDC

200 papers

Stochastically driven nonlinear processes limit the number of amplified modes in a natural system due to competitive mode interaction, which is accompanied by loss of coherence when increasing the complexity of system. Specifically, we find…

Optics · Physics 2016-07-21 Lei Gao , Tao Zhu , Stefan Wabnitz , Min Liu , Wei Huang

Pumping a nonlinear crystal by an intense radiation results in the optical parametric generation of photons in two modes (the signal and the idler). The quantized electromagnetic field in these modes is described by a continuous-variable…

Quantum Physics · Physics 2020-01-01 S. V. Vintskevich , D. A. Grigoriev , S. N. Filippov

The extraordinary properties of laser-induced transparency of a negative-index slab and parametric amplification for a backward-wave signal are investigated. The effects of the idler absorption and phase mismatch on the amplification of the…

Using broadband (12-45 THz) multi-terahertz spectroscopy, we show that stimulated Rayleigh scattering dominates the transient optical conductivity of cadmium arsenide, a Dirac semimetal, under an optical driving field at 30 THz. The…

We analyze a model where a closed $V$ system is excited by two uncorrelated partially coherent fields. We use a collisionally broadened CW laser, which is a good model for an experimentally realizable partially coherent field, and show that…

Quantum Physics · Physics 2015-05-06 Z. S. Sadeq

We theoretically and experimentally demonstrate coherence phenomena in optical parametric amplification inside a cavity. The mode splitting in transmission spectra of phase-sensitive optical parametric amplifier is observed. Especially, we…

Quantum Physics · Physics 2009-11-11 Hongliang Ma , Chenguang Ye , Dong Wei , Jing Zhang

Analytical expressions are derived for the distribution rates of spatial coincidences in the counting of photons produced by spontaneous parametric down conversion (SPDC). Gaussian profiles are assumed for the wave function of the idler and…

Quantum Physics · Physics 2016-05-05 Lorenzo M. Procopio , Oscar Rosas-Ortiz , Victor Velazquez

Speckle is a wave interference phenomenon that has been studied in various fields, including optics, hydrodynamics and acoustics. Speckle patterns contain spectral information of the interfering waves, and of the scattering medium that…

The twisted Gaussian Schell Model describes a family of partially coherent beams that present several interesting characteristics, and as such have attracted attention in classical and quantum optics. Recent techniques have been…

Stimulated emission tomography (SET) is an excellent tool for characterizing the process of spontaneous parametric down-conversion (SPDC), which is commonly used to create pairs of entangled photons for use in quantum information protocols.…

Quantum Physics · Physics 2024-07-04 Yang Xu , Saumya Choudhary , Robert W. Boyd

We present a theoretical and experimental analysis of the joint effects of the transverse electric field distribution and of the nonlinear crystal characteristics on the properties of photon pairs generated by spontaneous parametric…

Quantum Physics · Physics 2013-06-21 Roberto Ramirez-Alarcon , Hector Cruz-Ramirez , Alfred B. U'Ren

Nanoscale lasers sustain few optical modes so that the fraction of spontaneous emission $\beta$ funnelled into the useful (lasing) mode is high (of the order of few 10$^{-1}$) and the threshold, which traditionally corresponds to an abrupt…

It is known that a spatially partially coherent light field produces better imaging contrast compared to a spatially coherent field and that the contrast increases as the spatial coherence length of the field becomes smaller. The transverse…

The transverse mode of an atom laser beam that is outcoupled from a Bose-Einstein condensate is investigated and is found to be strongly determined by the mean--field interaction of the laser beam with the condensate. Since for repulsive…

Soft Condensed Matter · Physics 2009-11-07 Th. Busch , M. Köhl , T. Esslinger , K. Molmer

In the process of spontaneous parametric downconversion, photons from a pump field are converted to signal and idler photon pairs in a nonlinear crystal. The reversed process, or upconversion of these pairs back to single photons in a…

Quantum Physics · Physics 2015-05-14 Kevin A. O'Donnell , Alfred B. U'Ren

We demonstrate experimental generation of spatially-entangled photon-pairs by spontaneous parametric down conversion (SPDC) using a partial spatially coherent pump beam. By varying the spatial coherence of the pump, we show its influence on…

Quantum Physics · Physics 2019-05-29 Hugo Defienne , Sylvain Gigan

Irradiation of sharp silver tips with femtosecond laser pulses leads to photoassisted coherent field emission without a static field. We reconstruct the time profile of the emission, and show that the process is entirely governed by the…

Since the development of lasers, we have continuously sought to advance techniques and theory to obtain beams with a high degree of coherence, as natural light sources provide incoherent light. However, there are applications where it is…

Optics · Physics 2024-03-15 Gubio G. de Lima , Sinara S. Dourado

The Doppler effect of moving atoms can create irreversibility of light. We show that the laser field in electromagnetic induced transparency (EIT) scheme with atomic motion can control the directional propagation of two counter-propagating…

Quantum Physics · Physics 2008-07-23 C. H. Raymond Ooi

In this work we study the transverse spatial correlation of the pair of photons generated via the process of spontaneous parametric frequency down-conversion, in periodically poled non-linear crystals illuminated by a pulsed laser beam. It…

Quantum Physics · Physics 2009-06-26 O. Cosme , A. Delgado , G. Lima , C. H. Monken , S. Pádua