2022 Impact factor 2.8
Special Topics

News / Highlights / Colloquium

EPJ ST Highlight - CompactLight: Designing a Cost-Effective XFEL Facility

An international group of experts has produced a design for a free electron X-ray laser facility that is significantly smaller and cheaper than those that are currently in use.

Very many advances in structural science since the 1970s were made by probing materials with synchrotron radiation: that is, high energy X-rays generated through accelerating high-energy electrons. The latest generation of such sources, X-ray free electron lasers (XFEL) are far more powerful than their predecessors, but are only accessible to international consortia and a few rich countries because of their high cost. Now, an international group of experts have prepared a design for a more compact and cost-effective XFEL system, accessible to small countries and, perhaps, some individual laboratories. The design is published in EPJ Special Topics (EPJ ST).


EPJ ST Highlight - An exciting era for ultrafast science in France

Progress across five scientific topics currently being investigated by the French scientific network on ultrafast phenomena highlight both a rapid pace of discovery and emerging new directions of research.

From biochemistry to quantum mechanics, ultrafast phenomena can be found across a broad array of scientific fields. Now the subject of a rapidly expanding area of research, they describe how matter behaves over timescales ranging from picoseconds (thousandths of a nanosecond), down to attoseconds (billionths of a nanosecond).

Today, ultrafast processes are studied by a global community of scientists, who are dedicated to understanding the inner workings of matter, and exploring how they can be controlled and exploited for novel applications. In 2023, three researchers were awarded the Nobel Prize in Physics for their contribution to attosecond laser technology: clearly emphasising the growing relevance of the field.


EPJ ST Highlight - Capturing the evolution of complex quantum systems

Representing the HEOM mathematical structure

Through a new survey, researchers show how mathematical representations named ‘tensor trains’ can help to capture and simulate the dynamics of evolving quantum systems across a range of different scenarios.

Many quantum systems are heavily influenced by their surrounding environments, making them incredibly challenging to describe theoretically. To capture the dynamics and evolution of these systems, researchers often use mathematical representations named ‘tensor trains’. Through new research published in EPJ ST, a team of researchers from four different institutions in France show how tensor trains can be implemented to describe and simulate quantum systems.


EPJ ST Highlight - Many-body interactions feel the heat: Introducing thermal field theory

A many-body process at zero temperature which becomes much more complicated when temperature is a factor. Credit: Robert Lea

Thermal field theory seeks to explain many-body dynamics at non-zero temperatures not considered in conventional quantum field theory.

Quantum field theory is a framework used by physicists to describe a wide range of phenomena in particle physics and is an effective tool to deal with complicated many-body problems or interacting systems.

Conventional quantum field theory describes systems and interactions at zero temperature and zero chemical potential, and interactions in the real world certainly do occur at non-zero temperatures. That means scientists are keen to discover what effects may arise as a result of non-zero temperature and what new phenomena could arise due to a thermal background. In order to understand this, physicists turn to a recipe for quantum field theory in a thermal background — thermal field theory.

In a new paper in EPJ ST, Munshi G. Mustafa, Senior Professor at the Saha Institute of Nuclear Physics, Kolkata, India, introduces a thermal field theory in a simple way weaving together the details of its mathematical framework and its application.


EPJ ST Highlight - Investigating the Ising model with magnetisation

Evolution from paramagnetism to ferromagnetism.

Researchers have explored the evolution of systems of interacting spins, as they transition from random to orderly alignments. Through new simulations, they show that this evolution can be investigated by measuring the changing strength of the system’s magnetism.

The Ising model describes systems of interacting atomic spins relaxing from a ‘paramagnetic’ state – whose spins point in random directions, to a ‘ferromagnetic’ state – whose spins spontaneously align with each other. So far, the nonequilibrium dynamics of this transition has been studied by measuring the growth of regions, or ‘domains’ of aligned spins. In new research published in EPJ ST, researchers led by Wolfhard Janke at the University of Leipzig, Germany, show how this can be done far more easily by measuring the strength of the system’s magnetisation. The team’s discovery could help researchers to better understand the atomic-scale interactions underlying many different phenomena in nature: from electrostatic forces, to neuroscience and economics.


EPJ ST issue: Trends in Recurrence Analysis of Dynamical Systems

More than a decade has passed since the publication of the special issue “20 Years of Recurrence Plots: Perspectives for a Multi-purpose Tool of Nonlinear Data Analysis” in the European Physical Journal—Special Topics (EPJST). The hope for further developments inspired by the interesting contributions in this special issue was fully realized. We see an amazing development in the field of recurrence plots (RPs), recurrence quantification analysis (RQA), and recurrence networks. Recurrence analysis is not just one method; it has emerged as an entire framework with many extensions, special recurrence definitions, and specifically designed methods and tools. It has found spreading applications in diverse and growing scientific fields. Recurrence analysis has become a widely accepted concept, even referred to in studies that are actually not using it as a method, but rather using it as a reference or alternative tool. It continues to be an active area of research and development today. An attempt to provide an overview of the most significant technical developments of this recurrence-plot-based framework in the past decade is included in this special issue.

All articles are available here and are freely accessible until 8 May 2023. For further information read the Editorial by Norbert Marwan, Charles L. Webber & Andrzej Rysak ”Trends in recurrence analysis of dynamical systems” Eur. Phys. J. Spec. Top. 232, 1–3 (2023). https://doi.org/10.1140/epjs/s11734-023-00766-z.

EPJ ST Highlight - Tracking how magnetism affects animal behaviour

Behavioural testing of animal magnetic sensing in the laboratory and the wild.

We still know little about how animal behaviour changes in response to magnetic fields. A new review provides a tutorial introduction to the study of this fascinating and potentially useful phenomenon.

For over 50 years, scientists have observed that the behaviour of a wide variety of animals can be influenced by the Earth’s magnetic field. However, despite decades of research, the exact nature of this ‘magnetic sense’ remains elusive. Will Schneider and Richard Holland from Bangor University in Wales and their co-worker Oliver Lindecke from the Institute for Biology, Oldenburg, Germany have now written a comprehensive overview of this cross-disciplinary field, with an emphasis on the methodology involved. This work is now published in EPJ ST.


EPJ ST issue: Collective behavior of nonlinear dynamical oscillators

This topical issue collects contributions of recent achievements and scientific progress related to the collective behavior of nonlinear dynamical oscillators. The individual papers focus on different questions of present-day interest in this topic.

All articles are available here and are freely accessible until 16 March 2023. For further information read the Editorial by Sajad Jafari, Bocheng Bao, Christos Volos, Fahimeh Nazarimehr & Han Bao ”Collective behavior of nonlinear dynamical oscillators” Eur. Phys. J. Spec. Top. 231, 3957–3960 (2022). https://doi.org/10.1140/epjs/s11734-022-00725-0

EPJ ST Highlight - Dynamics of the COVID-19 pandemic

The outbreak of COVID-19 changed the human perception of day-to-day life and tested the bounds of medical technology in protecting the welfare of humans. Several approaches and safety measures have been implemented to minimize the countless lives that are being affected. However, public health and educational breaches are evidenced in most countries in which not all citizens have the same opportunities to deal with the pandemic. Therefore, this has led to pervasive consequences, including mental health problems because of the disruption of everyday life routines.

This special issue is a collection of 35 orginal research articles that address the dynamics and applications of COVID-19 through nonlinear dynamics. The articles are organized in five sections, comprising mathematical modeling and epidemics, the dynamics of several waves and transmission, neural network and deep learning related to COVID-19, predictions and estimations related to COVID-19, and detailed analysis on the pandemic and its applications. The various contributions report important, timely, and promising results and provide insight into the spread of the coronavirus and control measures against the COVID-19 pandemic.

All articles are available here and are freely accessible until 21 March 2023. For further information read the Editorial by Santo Banerjee ”Dynamics of the COVID-19 pandemic: nonlinear approaches on the modelling, prediction and control” Eur. Phys. J. Spec. Top. 231, 3275–3280 (2022). https://doi.org/10.1140/epjs/s11734-022-00724-1

EPJ ST Highlight - Showcasing the possibilities of memristor circuits

The papers presented in this special issue explore several unique capabilities of memristor-based systems: including multistability, nonlinearity, and chaotic dynamics

First demonstrated in 2008, the memristor is an electrical component which can limit the amount of current in a circuit, while remembering the amount of charge it conveyed in the past. Yet despite its numerous potential applications, the memristor’s commercial rollout has so far been restricted by the high manufacturing costs of its nano-scale electrical components.

To improve both the range of applications and theoretical understanding of memristors, there is a need to investigate their fundamental features, while diversifying the tools used to model their behaviours. In this special issue, the journal EPJ ST presents 25 new papers showcasing the widely-varied possibilities by memristor systems, and the mathematical principles required to understand and model them.


Managing Editors
Sandrine Karpe and Vijala Kiruvanayagam (EDP Sciences) and Sabine Lehr (Springer-Verlag)
Dear Isabelle,
Many thanks for all the hard work. Many thanks indeed!

Peter M.A. Sloot, University of Amsterdam, The Netherlands
Editor EPJ Special Topics 222/6, 2013

ISSN: 1951-6355 (Print Edition)
ISSN: 1951-6401 (Electronic Edition)

© EDP Sciences and Springer-Verlag