EPJ D Topical Issue: Precision Physics of Simple Atomic Systems
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- Published on 17 July 2023
Guest Editors: Krzysztof Pachucki, Thomas Udem, Wim Ubachs, Paolo Crivelli & Stefan Ulmer
This EPJD special issue dedicated to the field of precision physics of simple atomic systems includes several important peer-reviewed contributions, presented on the 11th edition of the PSAS conference —initially planned to take place in May 2020 in Wuhan, China (only to be rescheduled 2 years later, in May 2022, due to the COVID-19 pandemic, in Warsaw, Poland).
The aim of the PSAS conference is to gather scientists from all over the world working on precise calculations and measurements, with the goal to test fundamental physics, to verify laws of physics, and to determine fundamental constants. Correspondingly, a mix of theoretical, numerical and experimental works spanning the fields of spectroscopy of atomic and molecular hydrogen, QED of few-electron bound systems, exotic atoms and ions, searches for BSM physics with atoms and antimatter, clocks, measurements of g-2 and alpha, originating from several of the major groups in this field, are reported here, making the current collection of interest for both the younger generation entering this research field and experts for efficient access on recent developments.
All articles are available here and are freely accessible until 29 August 2023. For further information read the Editorial.
EPJ D Highlight - Testing a perfect absorber metamaterial
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- Published on 17 July 2023
The proposed metamaterial could have a wide range of applications, from sensing to stealth technology
Metamaterials are a type of artificial material which, as the prefix “meta” – meaning in Greek “after” or “beyond” – indicates, demonstrate electromagnetic properties and other characteristics not found in nature.
As a result of these characteristics, including negative refraction and perfect lensing and cloaking, which arise from the lattice design composition of these substances rather than the materials that actually comprise them, metamaterials have become a hot research topic.
In particular, materials scientists are actively hunting for metamaterials that are “perfect absorbers” of electromagnetic radiation with controllable resonance characteristics that lead to their wide usage in applications as varied as solar cells, thermal radiation imaging, sensing technology, and even stealth technology.
In a new paper in EPJ D, Shahzad Anwar, a researcher at the Department of Physics, Islamia College Peshawar, Pakistan, and his colleagues document the proposed design of a triple-band perfect metamaterial absorber. The new metamaterial could have applications in sensors, filters, and in stealth technology.
EPJ D Highlight - A broader approach to quantum walks
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- Published on 12 July 2023
Quantum walks have been widely studied for their ability to simulate real physical phenomena. Physicists previously studied two distinct types of quantum walk, but so far, they haven’t widely considered how their mathematical descriptions could be linked. Through new research published in EPJ D, a pair of physicists in France: Nicolas Jolly at ENS de Lyon, and Giuseppe Di Molfetta at Aix-Marseille University, show how ‘discrete-‘ and ‘continuous-time’ quantum walks can be described using more general mathematical language. Their results could allow researchers to simulate an even broader range of phenomena using quantum walks.
EPJ D Topical Issue: Dynamics of Systems on the Nanoscale (2021)
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- Published on 26 June 2023
Guest Editors: Alexey V. Verkhovtsev, Vincenzo Guidi, Nigel J. Mason, Andrey V. Solov’yov
Understanding the Dynamics of Systems on the Nanoscale forms the core of a multidisciplinary research area addressing many challenging interdisciplinary problems at the interface of physics, chemistry, biology, and materials science. They include problems of structure formation, fusion and fission, collision and fragmentation, surfaces and interfaces, collective electronic excitations, reactivity, nanoscale phase and morphological transitions, irradiation driven transformations of complex molecular systems, biodamage, channeling phenomena, and many more. Common to these interdisciplinary scientific problems is the central role of the structure formation and dynamics of animate and inanimate matter on the nanometer scale.
This topical issue presents a collection of research papers devoted to different aspects of the Dynamics of Systems on the Nanoscale, ranging from fundamental research on elementary atomic and molecular mechanisms to studies at a more applied level, covering innovative theoretical, experimental and computational modeling techniques. Some of the contributions discuss specific applications of the research results in several modern and emerging technologies, such as controlled nanofabrication with charged particle beams or the design and practical realization of novel gamma-ray crystal-based light sources.
EPJ D Highlight - Better understanding the bonds between carbon group elements
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- Published on 04 May 2023
Heating clusters of these elements reveals key differences
The bonds between clusters of elements in the fourteenth group of the periodic table are known to be fickle. Ranging from the nonmetal carbon, to the metalloids silicon and germanium, to the metals tin and lead, all these elements share the same configuration of valence electrons – electrons in their atoms’ outermost energy level. However, clusters formed from these elements respond differently to being excited with laser pulses. Studying the response of atomic clusters to photoexcitation as a function of the element they are composed of and their number of atoms reveals patterns that can be used to gain insight into their structure and binding mechanisms.
EPJ D Highlight - Predicting the composition of a steel alloy
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- Published on 04 May 2023
Austenitic steel is a potential material for nuclear fusion reactors
Producing energy on Earth through nuclear fusion, the type of reaction that powers the Sun, has proven to be a major challenge. The extreme conditions needed for such a reaction require the walls of a nuclear fusion device to be made of a material with a particular set of mechanical properties, including being able to withstand incredibly high temperatures and be shock- and corrosion-resistant. Austenitic steel, a non-magnetic steel with a crystalline structure, is one of the materials considered for use in nuclear fusion devices.
EPJ D Highlight - Atoms slow down more within colder blackbody radiation
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- Published on 10 February 2023
New analysis shows that atoms will encounter high frictional forces in the presence of blackbody radiation at lower temperatures. Accounting for this effect could help researchers to improve the accuracy of high-precision experiments.
Blackbody radiation (BBR) contains electromagnetic waves with characteristic spectra, which changes shape depending on the temperature of the body. When moving atoms encounter these fields, they experience a repulsive force which slows down their movement towards the source of the radiation. Through new analysis published in EPJ D, Vipul Badhan and colleagues at Guru Nanak Dev University, India, show that the influence of this ‘blackbody friction force’ (BBFF) is particularly strong at lower temperatures.
EPJ D Topical review - Theory and molecular simulations of plasma sputtering, transport and deposition processes
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- Published on 03 February 2023
A new Topical Review published in EPJD provides an overview of the basic theory of sputtering with recent models, focussing in particular on sputtered atom energy distribution functions. Models such as Monte-Carlo, kinetic Monte-Carlo, and classical Molecular Dynamics simulations are presented due to their ability to describe the various processes involved in sputtering, transport and deposition processes.
EPJ D Highlight - Alain Aspect: The physicist who made entanglement an experimental reality
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- Published on 23 January 2023
For Einstein and other physicists of his generation, the strongly counter-intuitive features of quantum mechanics were very hard to accept, given that our intuition is based on the classical world around us. This EPJ D Topical Issue examines the discoveries, motivations, and continuing legacy of Alain Aspect: the physicist whose experiments, along with those of John Clauser and Anton Zeilinger, have made that quantum entanglement, an essentially non-classical feature, is now also an experimental reality, exploited in science and technology.
EPJ D Topical Issue: Advances in Multi-Scale Modelling of Intense Electronic Excitation Processes
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- Published on 12 December 2022
Guest Editors: Jorge Kohanoff, Antonio Rivera, Eduardo Oliva Gonzalo, Andrey V Solov'yov and Tzveta Apostolova
Processes occurring in a target after irradiation span many orders of magnitude in space and time, which makes them intractable within a single rigorous approach. Typically, only partial aspects related to the radiation-induced effects in matter are treated. The lack of a systematic methodology to simulate the underlying phenomena hinders advances in various fields, and poses challenges to theoreticians, simulators, and experimentalists. It is therefore important to tackle this problem from a multi-scale perspective. This is the realm of this Topical collection, published in the Eur. Phys. J. D (EJPD Topical collection), which includes articles covering a wide range of methods, namely TDDFT, time-dependent Schrödinger equation in one or two-electron approximation, radiation Monte Carlo, Boltzmann transport equation, radiation-hydrodynamics and ab initio and classical Molecular Dynamics.
