Related papers: Time-resolved spectrum output from a grating spect…
We demonstrate that a semiconductor laser perturbed by the distributed feedback from a fiber random grating can emit light chaotically without the time delay signature. A theoretical model is developed based on the Lang-Kobayashi model in…
An emerging way to deal with high-dimensional non-euclidean data is to assume that the underlying structure can be captured by a graph. Recently, ideas have begun to emerge related to the analysis of time-varying graph signals. This work…
Flying plasma mirrors induced by intense lasers has been proposed as a promising way to generate few-cycle EUV or X-ray lasers. In addition, if such a relativistic plasma mirror can accelerate, then it would serve as an analog black hole to…
Real-time probing of electrons can uncover intricate relaxation mechanisms and many-body interactions hidden in strongly correlated materials. While experimenters have used ultrafast optical pump-probe methods in bulk materials, laser…
We study linear time dispersive and dissipative systems. Very often such systems are not conservative and the standard spectral theory can not be applied. We develop a mathematically consistent framework allowing (i) to constructively…
Nowadays, in Positron Emission Tomography (PET) systems, a Time of Flight information is used to improve the image reconstruction process. In Time of Flight PET (TOF-PET), fast detectors are able to measure the difference in the arrival…
We present a novel and quite general analysis of the interaction of a high-field chirped laser pulse and a relativistic electron, in which exquisite control of the spectral brilliance of the upshifted Thomson-scattered photon is shown to be…
We present a novel way to fit solar flare X-ray spectra that offers more sensitivity to physical flare parameters than traditional approaches to spectroscopy. We decouple physically distinct emission types in solar flare X-ray spectra using…
This paper presents a simplified theoretical model for the study of emission from laser produced plasma to better understand the processes and the factors involved in the onset of saturation in plasma emission as well as in increasing…
Dispersive Fourier transformation is a powerful technique in which spectral information is mapped into the time domain using chromatic dispersion. It replaces a spectrometer with an electronic digitizer, and enables real-time spectroscopy.…
The time-frequency content of a signal can be measured by the Gabor transform or windowed Fourier transform. This is a function defined on phase space that is computed by taking the Fourier transform of the product of the signal against a…
We measure the resonant forward scattering of light by a highly saturated atomic medium through the flashes emitted immediately after an abrupt extinction of the probe beam. The experiment is done in a dilute regime where the phenomena are…
Based on single particle tracking in the framework of classical Thomson scattering with incoherent superposition, we developed a fully relativistic, three dimensional numerical code that calculates and quantifies the characteristics of…
We present an exactly solvable model for photon emission, which allows us to examine the evolution of the photon wavefunction in space and time. We apply this model to coherent phenomena in three-level systems with a special emphasis on the…
While sensing in high temporal resolution is necessary for wide range of application, it is still limited nowadays due to cameras sampling rate. In this work we try to increase the temporal resolution beyond the Nyquist frequency, which is…
Time- and angle-resolved photoemission spectroscopy has played an important role in revealing the non-equilibrium electronic structures of solid-state materials. The implementation of high harmonic generation to obtain a higher photon…
The radioactive decay of unstable nuclei created in the rapid neutron capture process releases a large amount of $\gamma$-rays. When the ejecta are optically thick, these $\gamma$-rays may contribute to an associated kilonova. Once…
Extreme gravitational lensing and relativistic frequency shifts, combined together, imply that radiation emitted from a black hole's vicinity can echo at different frequencies and times, leading to spectrotemporal correlations in observed…
Long time ago, photon production was proposed as a probe and a thermometer for Quark-Gluon Plasma (QGP). However, only recently has the complete $\alpha_s$ order photon spectrum been obtained. In this paper we give a brief review of the…
In optics, a reflective grating is a conducting surface with a ripple. The typical use of such a grating involves an incident electromagnetic wave with wave vector k in the x-z plane, and interference effects lead to a discrete set of…