Nuclear Sciences & Technologies


EPJ H Highlight - Timeless thoughts on the definition of time

The solar year was often determined as the interval between consecutive spring equinoxes when the sun is directly over the equator.

On the evolution of how we have defined time, time interval and frequency since antiquity

The earliest definitions of time and time-interval quantities were based on observed astronomical phenomena, such as apparent solar or lunar time, and as such, time as measured by clocks, and frequency, as measured by devices were derived quantities. In contrast, time is now based on the properties of atoms, making time and time intervals themselves derived quantities. Today’s definition of time uses a combination of atomic and astronomical time. However, their connection could be modified in the future to reconcile the divergence between the astronomic and atomic definitions. These are some of the observations made by Judah Levine, author of a riveting paper just published in EPJ H, which provides unprecedented insights into the nature of time and its historical evolution.


EPJ C: New Editor-in-Chief for Experimental Physics II: Astroparticle Physics

The publishers of The European Physical Journal C – Particles and Fields are pleased to announce the appointment of Professors Laura Baudis as new Editor-in-Chief. This follows the splitting of the experimental section into Experimental Physics I: Accelerator Based High-Energy Physics, now led by Jos Engelen, and Experimental Physics II: Astroparticle Physics, now led by Laura Baudis.

Laura Baudis is a Professor at the University of Zurich. Her research interests are in astroparticle physics and cosmology, in particular in the fields of direct dark matter detection and neutrino physics.

EPJ AP Review - Imaging, single atom contact and single atom manipulations at low temperature

The LT-UHV-4-STM head and a 5.12 x 5.12 nm2 STM image of a letter C constructed atom by atom with 6 Au ad-atoms on Au(111) using here scanner PS3. I = 50 pA, V = 500 mV with ΔZ = 0.12 nm. Single atom manipulations tunnel resistance: 333 KΩ.

The new ScientaOmicron LT-UHV scanning tunneling microscope is installed at Pico-Lab CEMES-CNRS (Toulouse) with its 4 STM scanners performing on the same surface. At 4.3 K, we report state-of-the-art STM experiments on Au(111) usually performed on the most stable single tip LT-UHV scanning tunneling microscopes.

Operating the 4 scanners independently or in parallel with an inter tip apex distance lower than 100 nm, the ΔZ stability is better than 2 pm per STM. Single Au atom manipulations were performed on Au(111) recording the pulling, sliding or pushing signal. When contacting one Au ad-atom, a jump to contact leads to a perfect linear low voltage I-V characteristics with no averaging. Two tips surface conductance measurements were also performed with one lock-in and in a floating sample mode to capture the Au(111) surface states via two STM tips dI/dV characteristics. This new instrument is exactly 4 times as precise as a single tip LT-UHV STM.


EPJ E Highlight - New insights into the evaporation patterns of coffee stains

Deposits of silicon dioxide nanoparticles at pH2 and pH9 on glass substrates with driven menisci experiments

New factors influencing particle deposition via solvent evaporation and relevant to microchips manufacturing have now been elucidated

Few of us pay attention to the minutiae of coffee stains’ deposition patterns. However, physicists have previously explained the increased deposition of ground coffee particles near the edge of an evaporating droplet of liquid. They attributed it to the collective dynamics of ground coffee grains as the liquid evaporates along the contact line between the liquid coffee and the table. This kind of dynamics also governs microchip production, when particles are deposited on a substrate by means of solvent evaporation. However, until recently, explanations of how such evaporation patterns are formed did not account for the effect of the mutual interactions between electrically charged particles. Now, Diego Noguera-Marín from the University of Granada, Spain, and colleagues have found that particle deposition may be controlled by the interplay between the evaporation of the solvent via convection and the previously identified collective diffusion of suspension nanoparticles. These findings appear as part of an EPJ E topical issue, entitled Wetting and Drying: Physics and Pattern Formation.


EPJ E Highlight - How to make porous materials dry faster

A glass channel with a rectangular-like cross section closed at one end and open at the entrance for evporation. The receding air-water interface is qualitatively sketched

Physicists show that the shape of the air-water interface, when linked to capillarity, influences water retention or evaporation

Water in, water out: such is the cycle of porous material. In some cases, like with soils, it is preferable to keep water in. In others, it makes better economic and ecological sense to have porous materials dry faster, e.g. in the paper industries or with plasterboard manufacturing. Modeling how porous material retains water or dries up can be resolved by narrowing the focus down to a single porous channel; now, a team of physicists has uncovered subtle underlying effects. These include the local shape of the air and water interface, which, in turn, is influenced by the actual shape of the capillaries. Emmanuel Keita, a physicist from Paris-Est University, France, who is also affiliated with Harvard University, Massachusetts, USA, and colleagues have just published these results in EPJ E.


EPJ E Highlight - When liquids get up close and personal with powders

Schematic representation of the transfers of solvent to the polymer layer occurring during spreading, in the reference frame of the droplet

Scientists leave no stone unturned when studying how a liquid wets a powder

Every cook knows that dissolving powder into a liquid, such as semolina in milk or polenta in water, often creates lumps. What they most likely don’t know is that physicists spend a lot of time attempting to understand what happens in those lumps. In a review paper published in EPJ E, scientists from the École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI), France, share their insights following ten years of research into the wetting of soluble polymer substrates by droplets of solvents like water.


EPJ Plus Highlight - Scrutinising the tip of molecular probes

The solid lines indicate the temperature range used to estimate the amount of molecules loaded onto the probe.

Nature of interaction of probe molecules on the surface of oxide particles elucidated

Studies of molecules confined to nano- or micropores are of considerable interest to physicists. That’s because they can manipulate or stabilise molecules in unstable states or obtain new materials with special properties. In a new study published in EPJ Plus, Stefan Frunza from the National Institute of Materials Physics in Romania and colleagues have discovered the properties of the surface layer in probe molecules on the surface of oxide particles. These properties depend on the interaction at the interface. In this particular study, probes are formed by adsorption of rod-like cyanophenyl derivates on the surface of oxide particles. The authors found that their surface layers behave like glass-forming liquids.


EPJ Plus - Paolo Biscari becomes Deputy Editor-in-Chief

Professor Paolo Biscari

EPJ Plus has the great pleasure to announce the appointment of Professor Paolo Biscari as deputy Editor-in-Chief of the journal.

Paolo Biscari is Full Professor in Condensed Matter Physics at the Department of Physics of the Politecnico di Milano. At Politecnico di Milano he is Dean of the PhD School, which coordinates the researches of approximately 900 PhD candidates. He is Deputy Editor-in-Chief of the European Physical Journal Plus, and member of the Editorial Board of the Springer Book Series "Unitext". His research is focused in the soft matter area, and more specifically in liquid crystals, elastomers, and critical phenomena. He has been Invited Professor at the Universities of Southampton and Minnesota, has published more than 60 research papers in international peer-reviewed journals, three books, and has contributed to approximately 50 international congresses as Invited Speaker. He has directed as PI several research grants and contracts, awarded from both public Institutions and private companies. In 2004, he earned the Bruno Finzi Prize, awarded by the Istituto Lombardo, Accademia di Scienze e Lettere, for his research in Applied Mechanics.

EPJB Colloquium - Fulfillment of sum-rules and Goldstone modes in many body theories

Schematic representation of the two body mean field

This EPJ B Colloquium article explores applications of the Self-Consistent Random Phase Approximation (SCRPA) approach to Fermi systems with a continuously broken symmetry. Correlations beyond those considered by standard Random Phase Approximation (RPA) are summed up, thereby correcting for the quasi-boson approximation in standard RPA.


EPJ B Highlight - Helping turn waste heat into electricity

The resonant structure of electron scattering on the bismuth lattice.

How the collective motion of electrons interacting with crystal atoms can be fine-tuned to harvest excess heat

At the atomic level, bismuth displays a number of quirky physical phenomena. A new study reveals a novel mechanism for controlling the energy transfer between electrons and the bismuth crystal lattice. Mastering this effect could, ultimately, help convert waste heat back into electricity, for example to improve the overall efficiency of solar cells. These findings have now been published in EPJ B by Piotr Chudzinski from Utrecht University, the Netherlands.


G. Moutiers and A. Nicolas
ISSN: 2491-9292 (Electronic Edition)

© EDP Sciences

Conference announcements


Magnetic Island, Queensland, Australia, 22-24 July 2017