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Related papers: Chaotic imaging in frequency downconversion

200 papers

Femtosecond spectroscopy is an important tool for tracking rapid photoinduced processes in a variety of materials. To spatially map the processes in a sample would substantially expand the capabilities of the method. This is, however,…

Optics · Physics 2019-05-01 Ondřej Denk , Kaibo Zheng , Donatas Zigmantas , Karel Žídek

Stimulated emission tomography is a powerful and successful technique to both improve the resolution and experimentally simplify the task of determining the modal properties of biphotons. In the present manuscript we provide a theoretical…

The passive estimation of impulse responses from ambient noise correlations arouses increasing interest in seismology, acoustics, optics and electromagnetism. Assuming the equipartition of the noise field, the cross-correlation function…

We show that the symmetries of image formation by scattering enable graph-theoretic manifold-embedding techniques to extract structural and timing information from simulated and experimental snapshots at extremely low signal. The approach…

Computational Physics · Physics 2011-09-27 Peter Schwander , Chun Hong Yoon , Abbas Ourmazd , Dimitrios Giannakis

While there have been many publications on potential applications of chaos to fields such as communications, radar, sonar, random signal generation, channel equalization and others, designing continuous chaotic systems is still an unsolved…

Signal Processing · Electrical Eng. & Systems 2022-10-14 Thomas L. Carroll

We present an approach for improving spatial frequency sampling in active incoherent millimeter-wave (AIM) imaging systems using frequency diversity. AIM imaging relies on active transmission of spatio-temporally incoherent signals to…

Signal Processing · Electrical Eng. & Systems 2025-03-12 Jorge R. Colon-Berrios , Jeffrey A. Nanzer

The measurement of photon-number statistics of fields composed of photon pairs, generated in spontaneous parametric down-conversion and detected by an intensified CCD camera is described. Final quantum detection efficiencies, electronic…

Quantum Physics · Physics 2015-06-04 Jan Perina , Ondrej Haderka , Martin Hamar , Vaclav Michalek

This article is a theoretical and quantitative exploration of the limit regarding the pump intensity between the two regimes of spontaneous-parametric down-conversion (SPDC) as well as of four-wave-mixing (FWM) in the framework of a…

Quantum Physics · Physics 2026-02-04 Benoît Boulanger , Gaspar Mougin-Trichon , Véronique Boutou

The transient response of an intrinsic graphene, which is caused by the ultrafast interband transitions, is studied theoretically for the range of pumping correspondent to the saturated absorption regime. Spectral and temporal dependencies…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 F. T. Vasko

Spontaneous parametric down-conversion (SPDC) is a widely used process to prepare entangled photon pairs. In SPDC, a second-order nonlinear crystal is pumped by a coherent laser beam to generate photon pairs. The photon pairs are usually…

Quantum Physics · Physics 2024-09-16 Richard Bernecker , Baghdasar Baghdasaryan , Stephan Fritzsche

We investigate chaotic dynamical systems for which the intensity of trajectories might grow unlimited in time. We show that (i) the intensity grows exponentially in time and is distributed spatially according to a fractal measure with an…

Chaotic Dynamics · Physics 2015-03-26 Eduardo G. Altmann , Jefferson S. E. Portela , Tamás Tél

We investigate the 3D stationary flow of a weakly conducting fluid in a cubic cavity, driven by the Lorentz force created by two permanent magnets and a weak constant current. Our goal is to determine the conditions leading to efficient…

We show that finite-size, disordered molecular networks can mediate highly efficient, coherent excitation transfer which is robust against ambient dephasing and associated with strong multi-site entanglement. Such optimal, random molecular…

We theoretically study and experimentally demonstrate controlled generation of spatial modes of light via stimulated parametric downconversion (StimPDC) by transferring the spatial structure of a pump beam to the stimulated idler beam. We…

Very low intensity and phase fluctuations are present in a bright light field such as a laser beam. These subtle quantum fluctuations may be used to encode quantum information. Although intensity is easily measured with common…

Quantum Physics · Physics 2009-11-13 Alessandro S. Villar

Converting the medium infrared field to the visible band is an effective image detection method. We propose a comprehensive theory of image up-conversion under continuous optical pumping, and discuss the relationship between the…

We experimentally show that the response of a quantum-chaotic system can display resonance lines sharper than the inverse of the excitation duration. This allows us to discriminate two neighboring frequencies with a resolution nearly 40…

Quantum Physics · Physics 2007-05-23 Pascal Szriftgiser , Jean Ringot , Dominique Delande , Jean Claude Garreau

To make predictions or design control, information on local sensitivity of initial conditions and state-space contraction is both central, and often instrumental. However, it is not always simple to reliably determine instability fields or…

New chaos-based communication schemes for transmission of analog and digital information are suggested. The carrier signal is produced by chaotic generator having well-defined oscillation phases at least on short time intervals. For data…

Chaotic Dynamics · Physics 2017-08-10 Olga B. Isaeva , Alexey Yu. Jalnine , Sergey P. Kuznetsov

We present a new chaotic system of three coupled ordinary differential equations, limited to quadratic nonlinear terms. A wide variety of dynamical regimes are reported. For some parameters, chaotic reversals of the amplitudes are produced…

Chaotic Dynamics · Physics 2012-03-05 Christophe Gissinger