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Coherence refers to correlations between field vibrations at two separate points in degrees of freedom such as space, time, and polarisation. In the context of space, coherence theory has been formulated between two transverse positions…

A calibration scheme is presented for improved polarization state measurement of terahertz pulses. In this scheme the polarization response of a two-contact terahertz photoconductive detector is accurately measured, and is used to correct…

Optics · Physics 2012-01-25 M. Neshat , N. P. Armitage

The ability to measure polarisation, spectrum, temporal dynamics, and spatial amplitude and phase of optical beams is essential to study fundamental phenomena in laser dynamics, telecommunications and nonlinear optics. Current…

A major issue in harmonic analysis is to capture the phase dependence of frequency representations, which carries important signal properties. It seems that convolutional neural networks have found a way. Over time-series and images,…

Signal Processing · Electrical Eng. & Systems 2019-07-02 Stéphane Mallat , Sixin Zhang , Gaspar Rochette

An analysis of the matrix models representing the polarimetric properties of light and material media is carried out by using the concept of the coherency matrix, which leads to the identification and definition of their corresponding…

Optics · Physics 2020-02-18 José J. Gil

The mutual intensity and its equivalent phase-space representations quantify an optical field's state of coherence and are important tools in the study of light propagation and dynamics, but they can only be estimated indirectly from…

Optics · Physics 2017-11-16 Chenglong Bao , George Barbastathis , Hui Ji , Zuowei Shen , Zhengyun Zhang

In a cycle of papers, starting with the present one, a fundamental possibility of the polarization sounding of a pulsar magnetosphere using pulsar self-radiation as a test signal will be considered. The main idea of such a sounding is based…

Astrophysics of Galaxies · Physics 2014-11-25 O. M. Ulyanov , A. I. Shevtsova , A. O. Skoryk

Pulsar radio emission and its polarization are observed to evolve with frequency. This frequency dependence is key to the emission mechanism and the structure of the radio beam. With the new Ultra-Wideband receiver (UWL) on the Parkes radio…

High Energy Astrophysical Phenomena · Physics 2020-06-17 Lucy Oswald , Aris Karastergiou , Simon Johnston

High-harmonic spectroscopy driven by circularly-polarized laser pulses and their counter-rotating second harmonic is a new branch of attosecond science which currently lacks quantitative interpretations. We extend this technique to the…

Atomic Physics · Physics 2019-09-04 Denitsa Baykusheva , Simon Brennecke , Manfred Lein , Hans Jakob Wörner

Precision measurements in storage rings are increasingly limited by the ability to monitor collective spin dynamics coherently over long time scales. Existing polarimetry techniques rely on destructive scattering processes that preclude…

Pulsar timing, i.e. the analysis of the arrival times of pulses from a pulsar, is a powerful tool in modern astrophysics. It allows us to measure the time delays of an electromagnetic signal caused by a number of physical processes as the…

Instrumentation and Methods for Astrophysics · Physics 2025-02-04 Konstantin A. Postnov , Nataliya K. Porayko , Maxim S. Pshirkov

Coherent control over photoelectron wavepackets, via the use of polarization-shaped laser pulses, can be understood as a time and polarization-multiplexed process. In this work, we investigate this multiplexing via computation of the…

Atomic Physics · Physics 2016-05-30 Paul Hockett , Matthias Wollenhaupt , Thomas Baumert

The state of polarization and the carrier phase drift dynamically during transmission in a random fashion in coherent optical fiber communications. The typical digital signal processing solution to mitigate these impairments consists of two…

Information Theory · Computer Science 2024-01-25 Cristian B. Czegledi , Erik Agrell , Magnus Karlsson , Pontus Johannisson

An example of a coherent measurement for the direct evaluation of the degree of polarization of a single-mode optical beam is presented. It is applied to the case of great practical importance where depolarization is caused by polarization…

Quantum Physics · Physics 2015-06-26 N. Gisin

We have analyzed the polarization properties of pulsars at an observing frequency of 4.9 GHz. Together with low frequency data, we are able to trace polarization profiles over more than three octaves into an interesting frequency regime. At…

Astrophysics · Physics 2007-05-23 A. von Hoensbroech , J. Kijak , A. Krawczyk

The increased sensitivity of future radio telescopes will result in requirements for higher dynamic range within the image as well as better resolution and immunity to interference. In this paper we propose a new matrix formulation of the…

Astrophysics · Physics 2014-11-18 Chen Ben-David , Amir Leshem

We present a detailed mathematical analysis of the Fourier response of binary pulsar signals whose frequencies are modulated by circular orbital motion. The fluctuation power spectrum of such signals is found to be \nu_orb-periodic over a…

Astrophysics · Physics 2009-11-07 S. Jouteux , R. Ramachandran , B. W. Stappers , P. Jonker , M. van der Klis

The diverse polarization properties in pulsars are in conflict with applying a unique emission mechanism to the population. The polarization position angle (PPA) traverse in most pulsars shows a S-shaped curve that can be interpreted using…

High Energy Astrophysical Phenomena · Physics 2023-03-01 Dipanjan Mitra , George I. Melikidze , Rahul Basu

We present a large sample of high-precision, coherently-dedispersed polarization profiles of millisecond pulsars (MSPs) at frequencies between 410 and 1414 MHz. These data include the first polarimetric observations of several of the…

Astrophysics · Physics 2009-10-31 I. H. Stairs , S. E. Thorsett , F. Camilo

The propagation of wave fields and their interactions with matter are important for established and emerging fields in optical sciences. Efficient methods for predicting such behaviour have been employed routinely for coherent sources.…