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This article presents the experimental observations and characterization of Ion Acoustic Soliton (IAS) in a unique Multi-pole line cusp Plasma Device (MPD) device in which the magnitude of the pole-cusp magnetic field can be varied. And by varying the magnitude of the pole-cusp magnetic field, the proportions of two-electron-temperature components in the filament-produced plasmas of MPD can be varied. The solitons are experimentally characterized by measuring their amplitude-width relation and Mach numbers. The nature of the solitons is further established by making two counter-propagating solitons interact with each other. Later, the effect of the two-temperature electron population on soliton amplitude and width is studied by varying the magnitude of the pole cusp-magnetic field. It has been observed that different proportions of two-electron-temperature significantly influence the propagation of IAS. The amplitude of the soliton has been found to be following inversely with the effective electron temperature (Teff), Comment: arXiv admin note: text overlap with arXiv:2208.00279

This paper presents the detailed study of the controlled experimental observation and characterization of Ion Acoustic soliton in the quiescent argon plasma produced by filamentary discharge and confined in a multi-pole line cusp magnetic field device named Multi-pole line Cusp Plasma Device (MPD). In this system, the electrostatic fluctuations are found to be less than 1%, a characteristic of quiescent plasma. Ion acoustic soliton has been excited in MPD, and its propagation velocity and width of them are measured experimentally and compared with the 1-D Korteweg-de Vries (KdV) equation. The interaction of two counter-propagating solitons is also investigated to confirm propagation's solitary nature further. After the successful characterization of ion-acoustic soliton, the effect of varying the cusp magnetic field on the propagation of ion-acoustic soliton has been studied. It is experimentally observed in MPD that the pole cusp magnetic field value influences the excitation and propagation of solitons. The soliton amplitude increases with the pole field up to some value Bp~0.6kG, then decreases with the further increase in field values. Meanwhile, the width of the soliton shows different behavior. The role of primary electron confinement by cusp magnetic field geometry has been used to explain the observed results.

First Principles calculations are performed on the cubic bulk and its (001) surface of CsPbBr3 to reveal its electronic and optoelectronic properties. Various calculation schemes like GGA, GGA+SOC and the highly accurate modified Becke Johnson potential (mBJ) are applied. The electronic energy band gap calculations obtained from mBJ shows close approximity with the available experimental results. The cubic bulk phase is investigated for its mechanical stability and is found to bypass other structural phases. The optical absorption of both the bulk and the surface surpasses non-lead based cubic halides and zinc-based organic-inorganic hybrids.

The deployment of cellular spectrum in licensed, shared and unlicensed spectrum demands wideband sensing over non-contiguous sub-6 GHz spectrum. To improve the spectrum and energy efficiency, beamforming and massive multi-antenna systems are being explored which demand spatial sensing i.e. blind identification of vacant frequency bands and direction-of-arrival (DoA) of the occupied bands. We propose a reconfigurable architecture to perform spatial sensing of multi-band spectrum digitized via wideband radio front-end comprising of the sparse antenna array (SAA) and Sub-Nyquist Sampling (SNS). The proposed architecture comprises SAA pre-processing and algorithms to perform spatial sensing directly on SNS samples. The proposed architecture is realized on Zynq System on Chip (SoC), consisting of the ARM processor and FPGA, via hardware-software co-design (HSCD). Using the dynamic partial reconfiguration (DPR), on-the-fly switching between algorithms depending on the number of active signals in the sensed spectrum is enabled. The functionality, resource utilization, and execution time of the proposed architecture are analyzed for various HSCD configurations, word-length, number of digitized samples, signal-to-noise ratio (SNR), and antenna array (sparse/non-sparse)., Comment: 16 pages, 13 figures

In this letter, we propose space-time spreading (STS) of local sensor decisions before reporting them over a wireless multiple access channel (MAC), in order to achieve flexible balance between diversity and multiplexing gain as well as eliminate any chance of intrinsic interference inherent in MAC scenarios. Spreading of the sensor decisions using dispersion vectors exploits the benefits of multi-slot decision to improve low-complexity diversity gain and opportunistic throughput. On the other hand, at the receive side of the reporting channel, we formulate and compare optimum and sub-optimum fusion rules for arriving at a reliable conclusion.Simulation results demonstrate gain in performance with STS aided transmission from a minimum of 3 times to a maximum of 6 times over performance without STS., Comment: 5 pages, 5 figures

Time-varying diamagnetism in laser-produced plasma moving across the transverse magnetic field with different field strengths has been studied using fast imaging and magnetic probe. The emphasis of the present work is on the development of suitable B-dot probe and quantitative analysis of induced diamagnetic field in an expanding plasma plume. A Helmholtz coil associated with pulsed power system is used to produce uniform magnetic field of different strengths. Helmholtz coil allowed the plume imaging along the magnetic field lines, which gives the direct structural information of the induced diamagnetic cavity. A high frequency three-axis B-dot probe has been developed to measure the transient magnetic field. Different experimental approaches have been used to test the response, sensitivity and calibration of the developed probe. Findings indicate that plasma plume shows the perfect diamagnetic behaviour for the external field varying from 0.13 T to 0.57 T where the induced magnetic field almost completely displaced the external magnetic field., Comment: 18 pages, 14 figures

An experimental investigation of laser produced colliding plasma of aluminium target in the presence of external magnetic field in vacuum is done. Characteristic parameters and line emission of plasma plume in the presence of magnetic field are compared with those for field free case. Axial expansion of the plasma is slowed down in the presence of magnetic field as compared to the field free case. Contrary to the field free case no sharp interaction zone is observed. Higher electron temperature and increased ionic line emission from singly as well as doubly ionized aluminium can be attributed to the Joule heating phenomenon., Comment: 5 pages, 6 figures, Journal article

Composition analysis of LiF-C thin film for neutral and ionic contributions in Front Ablation (FA) and Back Ablation (BA) geometries in vacuum and 2\times10-1 mbar argon has been done. Temporal evolution of ionic to neutral ratio and neutral abundance for both the geometries has been estimated. For neutral abundance, two approaches viz Atomic Data and Analysis Structure (ADAS) analysis as well as integrated intensity ratio of Li I 670.1 nm and Li I 610.3 nm lines assuming LTE conditions are explored. The present attempt will be interesting from the view point of understanding the evolution of plasma composition in various geometries/configurations of laser ablation which has important implications in various applications e.g. pulsed laser deposition and laser cleaning., Comment: This manuscript is of 17 pages and has 12 figures