News
EPJ E Topical Issue on Thermal Non-Equilibrium Phenomena in Fluid Mixtures
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- Published on 12 October 2022
When a temperature difference, or gradient, is applied over a bulk fluid mixture at equilibrium, the phenomenon known as thermodiffusion, or the Ludwig-Soret effect, may occur. The thermal force will in general cause the components in the mixture to migrate until the thermal force is balanced by concentration gradients. If the thermal force is applied to a colloidal suspension, the colloids drift towards cold or hot regions. This phenomenon is commonly referred to as thermophoresis. If the fluid is soaked in a porous medium, an additional effect known as thermos-osmosis may occur. Thermo-osmosis leads to a pressure difference. These effects are different from normal diffusion and osmosis, where a concentration difference is the driving force.
EPJ Quantum Technology: New Review Article The Deep Space Quantum Link (DSQL)
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- Published on 12 October 2022
Space-based quantum optical links support future networking applications for quantum sensing, quantum communications, and quantum information science. In addition, such links enable new scientific experiments impossible to reach in terrestrial experiments. The Deep Space Quantum Link (DSQL) is a spacecraft mission concept that aims to use extremely long-baseline quantum optical links to test fundamental quantum physics in novel special and general relativistic regimes.
In a new Review article just published in EPJ Quantum Technology, an international author team provide an overview of a two-year long study of how quantum optics in space could be used to conduct new tests of fundamental physics, in compliment to proposed tests utilizing matter or clocks. The manuscript describes the findings of the NASA-funded study, and describes some of the technology requirements and outstanding mission design studies necessary to move forward with the mission.
EPJ D Colloquium - Electron scattering processes: fundamentals, challenges, advances, and opportunities
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- Published on 05 October 2022
Perspectives of a global team of experts on recent and significant advances and challenges in the electron scattering field
Over the past several decades, significant efforts of the electron-scattering community have been devoted to achieving an in-depth and comprehensive understanding of processes that involve low-energy electron interactions with diverse targets, ranging from atoms to complex systems.
EPJD supports public lecture by Nobel Laureate William D Phillips
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- Published on 30 September 2022
EPJD is proud to support the forthcoming public lecture by Nobel Laureate William D Phillips on "Time, Einstein and the Coolest Stuff in the Universe". All are welcomed to join this lecture online at the following
link https://www.youtube.com/watch?v=rgErE2FXCgI
on October 4th 2022
6pm EEST / 5pm CET / 4pm BST / 9am EDT
EPJ ST Highlight - Elastic nozzles could create more stable liquid jets
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- Published on 27 September 2022
New experiments show that nozzles which deform as liquid flows through them could help to improve the stability of liquid jets in many different scenarios
When a liquid jet is squirted through a nozzle, it will eventually break up into a string of droplets. Through previous studies, researchers determined that the distance from the nozzle where this breakup occurs depends on a wide range of factors: including the nozzle’s shape, and the movement of air surrounding the jet. So far, however, little attention has been paid to elastic nozzles, which can deform as liquids pass through them. Through new research published in EPJ ST, a team led by Andrew Dickerson at the University of Tennessee, USA, introduces the concept of passively-deforming nozzles, and shows that softer nozzle materials can produce more stable jets across a wide range of flow rates.
Johan Åkerman joins the EPJ Scientific Advisory Committee (SAC)
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- Published on 22 September 2022
The Scientific Advisory Committee of EPJ is delighted to welcome Dr. Johan Åkerman as the new representative for the Swedish Physical Society.
Johan Åkerman is the head of the Applied Spintronics Group at the Physics Department of University of Gothenburg. His expertise is in spintronic devices, such as magnetic tunnel junctions and MRAM, and more recently with spin torque and spin Hall nano-oscillators for microwave and spin wave signal generation, neuromorphic computing, and Ising Machines. He is one of the founding members of the Global Young Academy and the Swedish Young Academy, a fellow of the American Physical Society, and a member of the Royal Swedish Academy of Engineering Sciences.
EPJ H Highlight - Fermi’s ground-breaking figure
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- Published on 22 September 2022
How the radial wave function transformed physics
One way to better understand an atom is to shoot a particle at it and infer the atom’s properties based on how the particle bounces off it. In the mid-1930s, the physicist Enrico Fermi showed that one measurable number – the scattering length – illuminated everything that could be known about an electron scattering off an atom, or a neutron scattering off a nucleus. In a new paper in EPJ H: Historical Perspectives on Contemporary Physics, Chris Gould from North Carolina State University in Raleigh, USA, explains how Fermi’s simple sketch of a radial wave function laid the groundwork for a better understanding of low energy scattering phenomena, and led in turn to the concept of the pseudopotential, widely used in many areas of physics, including ultracold atom research and studies of qubits in realisations of quantum computers.
EPJ ST Highlight - Tiny animal hairs could act as sensitive compass needles
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- Published on 20 September 2022
Statistical mechanics shows that some animals may be able to perceive Earth’s magnetic field with bundles of microscopic hairs in their inner ears.
The exact mechanisms animals use to sense the direction of Earth’s magnetic field have long remained a mystery. One leading theory suggests that this ability is tied to bundles of microscopic hair cells in the inner ears. Through new research published in EPJ ST, Kirill Kavokin at St Petersburg State University, Russia, uses statistical analysis to show that just around 100 of these hair cells could act as effective biological compass needles, allowing animals to accurately sense the magnetic field surrounding them.
EPJ Plus Highlight - Modelling the use of Beta Radiation in cancer treatment
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- Published on 20 September 2022
New research pits the simulation of beta radiation doses in tumour treatment against an analytical method.
Treating superficial skin tumours especially when they are located above cartilage or bone with beta radiation can help protect sensitive structures during the delivery of treatment.
The use of short-range beta radiation in cancer treatment is not without its disadvantages, however, especially when it comes to the measurement of radiation exposure — dosimetry. When experimental dosimetry is not feasible, researchers use simulations and calculations to study the interaction of the ionizing radiation with matter and estimate the radiation dose delivered to a target organ.
A new paper published in EPJ Plus and authored by Eduardo De Paiva, from the Division of Medical Physics at the Institute of Radiation Protection and Dosimetry, Rio de Janeiro, Brazil, and his colleagues, pits the gold standard of simulation techniques — Monte Carlo (MC) simulation — against an alternative analytic method, the Loevinger formula.
EPJ E Colloquium - Thermophoresis and thermal orientation of Janus nanoparticles in thermal fields
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- Published on 02 September 2022
Thermal gradients induce thermodiffusion in aqueous solutions and liquid mixtures and thermophoretic forces that drive the motion of colloids towards hot or cold regions. The Soret coefficient quantifies the strength of the thermophoretic force and varies with temperature, colloid mass and diameter, and colloid-solvent interactions. Janus colloids (JCs ) are nanoparticles with heterogeneous compositions and two contrasting properties, or "two faces" like the Roman god Janus. For example, in spherical JCs, one hemisphere might be hydrophilic and the other hydrophobic. The interest in JCs has grown steadily given their applicability in materials science. While the behaviour of JCs under equilibrium conditions has been explored, their response to thermal gradients is still not fully understood. Explaining the behaviour of JCs in a thermal field might expand their use in materials science and biomedical applications.
