A Measure of Variability in Comovement for Economic Variables: a Time-Varying Coherence Function Approach [PDF]
In this paper, we suggest a different dynamic measure of comovement which is unlike previous studies allowing to test instability in comovement between two non stationary economic time series. We use the frequency approach, which is based on evolutionary
Mohamed Boutahar, Essahbi Essaadi
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Controlling the Spatial Coherence of an Optical Source Using a Spatial Filter
Applied Sciences, 2018 This paper presents the theory for controlling the spectral degree of coherence via spatial filtering. Starting with a quasi-homogeneous partially coherent source, the cross-spectral density function of the field at the output of the spatial filter is ...
Milo W. Hyde
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Twisted Electromagnetic Multi-Gaussian Schell-Model Pulsed Source and Its Propagation
IEEE Photonics Journal, 2021 Here, a novel family of random electromagnetic sources (twisted electromagnetic multi-Gaussian Schell-model pulsed beams) exhibiting transverse orbital angular momentum is proposed.
Yan Li, Ming Gao
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Coherence automatic adjustment of the optical pulses inside mode-lock fiber laser cavity [PDF]
, 2018 In the current work we demonstrate mode-locked fiber laser with automatic adjustment a coherence degree of the output pulses. As a source of the pulses we used 8-figure fiber laser with two amplifying fibers inside both loops of the laser cavity.
Alexey Kokhanovskiy +7 more
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Coherence-induced Polarization Effects in Vector Vortex Beams
, 2020 We demonstrate theoretically and experimentally coherence-induced polarization changes in generic and higher-order vector vortex beams with polarization singularity.
Manisha (13435638) +4 more
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PhotonicsIn this paper, the coherent properties of partially coherent Bessel–Gaussian optical beams propagating through a uniform medium (free space) or a turbulent atmosphere are examined theoretically.
Igor Lukin, Vladimir Lukin
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Effective degree of coherence : general theory and application to electromagnetic fields
, 2007 The concept of overall or effective degree of coherence has proven useful and insightful in the scalar theory of light. In this paper we extend the concept to fields represented over arbitrary vector (Hilbert) spaces. We show that the effective degree of
Friberg, Ari T., +2 more
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Variable numerical-aperture temporal-coherence measurement of resonant-cavity LEDs
, 2003 The first interferometric measurements of temporal-coherence length variation with numerical aperture (NA) are described for 650 nm, resonant-cavity light-emitting diodes (LEDs) agreeing with spectrally derived results.
Coutinho, RC +6 more
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Besinc Pseudo-Schell Model Sources with Circular Coherence
Applied Sciences, 2019 Partially coherent sources with non-conventional coherence properties present unusual behaviors during propagation, which have potential application in fields like optical trapping and microscopy.
Rosario Martínez-Herrero +4 more
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Suppression of Speckle Noise in Digital Holography With Spatial and Temporal Domain Depolarization
IEEE Access, 2020 Speckle noise in digital holography has a great influence on image quality, and one of the reasons for the formation of speckle noise is that the degree of coherence for the reference light and the object light is too high and unnecessary noise is ...
Tongyao Du +4 more
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