2016 Impact factor 1.461
Condensed Matter and Complex Systems

News / Highlights / Colloquia

EPJ B Colloquium - Nanophononics: state of the art and perspectives

Schematic of a cavity optomechanical system

Understanding vibrations in condensed matter, and in particular how to control these vibrations, is proving essential both at a fundamental level and for the development of a broad variety of technological applications. Intelligent design of the band structure and transport properties of phonons at the nanoscale, including their interactions with electrons and photons, has improved the efficiency of nanoelectronic systems and thermoelectric materials, permitted the exploration of quantum phenomena with micro- and nanoscale resonators, and provided new tools for spectroscopy and imaging.


EPJ B Highlight - Conductor turned insulator amid disorder

The fractal structure of the spatial spread of electrons in two-dimensional model of a spatially disordered lattice.

Study analyses how disorder in the way atoms are connected in a material influences electric conductivity

Some materials that are inherently disordered display unusual conductivity, sometimes behaving like insulators and sometimes like conductors. Physicists have now analysed the conductivity in a special class of disordered materials. Martin Puschmann from the Technical University Chemnitz, Germany, and colleagues have demonstrated that electrons in the materials studied display a multifractal spatial structure at the transition between conductive and insulating behaviour. These findings have just been published by in EPJ B.


EPJ B Highlight - Trapping climate pollutant methane gas in porous carbon

Schematic diagram of the confined lattice gas model used in some of the study’s calculations.

New adsorption of gas into porous carbon simulations are of interest to energy research and climate change mitigation

As talks of global warming are once again making headlines, scientists have renewed their efforts to understand how to best limit its effects. For example, sequestrating short-lived climate pollutants, such as methane and black carbon, yields much faster reductions in global warming compared to reductions in CO2. To do so, it is essential to have a better grasp of the nature of physico-chemical properties of gases interacting with porous carbon. Now, a team of chemical engineering researchers based in South Africa has established ways of accurately simulating methane adsorption and desorption in carbon with nanopores. These findings have been published by Matthew Lasich and Deresh Ramjugernath from the University of KwaZulu-Natal, Durban, South Africa, in EPJ B. Alternative applications for such findings are relevant for future energy research, such as energy storage and the development of natural gas extraction methods.


EPJ B Colloquium: Hierarchy of scales in language dynamics

The naming game

Language is a collective phenomenon, shared by a group of speakers, and originating from interactions between individual group members. This dimension has captured the interest of statistical physicists who have applied their methods to study how languages change and differentiate themselves from one another over time.


EPJ B Highlight - Anti-clumping strategy for nanoparticles

Schematic representation for a functionalized nanoparticle (NP) in brine.

Scientists identify the factors involved in preventing nanoparticles used in industrial applications from aggregating

Nanoparticles are ubiquitous in industrial applications ranging from drug delivery and biomedical diagnostics to developing hydrophobic surfaces, lubricant additives and enhanced oil recovery solutions in petroleum fields. For such nanoparticles to be effective, they need to remain well dispersed into the fluid surrounding them. In a study published in EPJ B, Brazilian physicists identified the conditions that lead to instability of nanoparticles and producing aggregates. This happens when the electric force on their surface no longer balances by the sum of the attractive or repulsive forces between nanoparticles. These findings were recently published by Lucas de Lara from the Centre for Natural and Human Sciences, at the University Federal of ABC (UFABC) in Santo André, SP, Brazil and colleagues.


EPJB Colloquium: Modern temporal network theory

Illustration by Mi Jin Lee

The power of any kind of network approach lies in its ability to simplify a complex system so as to better understand its function as a whole. Sometimes it is beneficial, however, to include more information than is available in a simple graph of nodes and links. Adding information related to the timing of interactions can facilitate more accurate predictions, as well as a deeper mechanistic understanding.


EPJ B Highlight - Surfing over simulated ripples in graphene

Effect of the simulated deformation of a physical feature (the local density of state) of an optical lattice analogue of graphene in curved space.

Scientists from India elucidate the theory governing the characteristics of curved or rippled graphene using a simulation model based on an optical lattice

The single-carbon-atom-thick material, graphene, featuring ripples is not easy to understand. Instead of creating such ripples physically, physicists investigating this kind of unusually shaped material rely on a quantum simulator. It is made up of an artificial lattice of light - called ultra-cold optical lattice - akin to eggs held in the cavities of an egg tray. This approach allowed a team of theoretical physicists from India to shed some light - literally and figuratively - on the properties of rippled graphene. These findings have just been published in EPJ B by Tridev Mishra and colleagues from the Birla Institute of Technology and Science, in Pilani, India. Ultimately, this work could find applications in novel graphene-based sensors.


EPJ B Highlight - Shaping the hilly landscapes of a semi-conductor nanoworld

Redeposition on hexagonally arranged dots.

A new study reveals how hexagonal-patterned, self-organised hill structures emerge in 2D at the nanoscale due to redeposition following semi-conductor bombardment with low-energy ions

Nanoscale worlds sometimes resemble macroscale roller-coaster style hills, placed at the tip of a series of hexagons. Surprisingly, these nanohills stem from the self-organisation of particles – the very particles that have been eroded and subsequently redeposited following the bombardment of semi-conductors with ion beams. Now, a new theoretical study constitutes the first exhaustive investigation of the redeposition effect on the evolution of the roughening and smoothing of two-dimensional surfaces bombarded by multiple ions. The results demonstrate that the redeposition can indeed act as stabilising factor during the creation of the hexagonally arranged dot patterns observed in experiments. These findings by Christian Diddens from the Eindhoven University of Technology, in the Netherlands, and Stefan Linz, from Munster University, Germany, have been published in a study published in EPJ B.


EPJ B Highlight - Law governing anomalous heat conduction revealed

Heat conductance as the function of temperature T for different lattice size N = 50; 100; 200; 400; 800 and 1600.

Study finds the law governing how heat transport scales up with temperature

How heat travels, matters. Yet, there is still no consensus on the exact physical mechanism that causes anomalous heat conduction - despite the existence of previous numerical simulation, theoretical predictions and experimental observations. Now, a team based in Asia has demonstrated that electron transport depends on temperature. It follows a scaling governed by a power law - and not the exponential scaling previously envisaged. These findings were recently published in EPJ B by Yunyun Li Tongji University, Shanghai, China, and colleagues in Singapore.


EPJ B Highlight - Structural shift elucidated with large-scale atomic simulations

Close-up view of a martensitic transformation from the Fe1-xNix crystallites in a large system at 348 K.

Iron-Nickel alloys’ structure changes as they heat up and cool down

Iron-nickel alloys are ubiquitous: they are found at the earth’s core and in meteorites. What is fascinating about such alloys is that their inner structure can change with rapid temperature swings. Heated up above 730 °C (1,340 °F), these alloys enter what is referred to as an austenitic phase. Alternatively, they can be turned into very hard alloys, referred to as a martensitic phase, by subjecting them to extremely rapid cooling. Now a team of scientists from Germany has, for the first time, created a large-scale simulation involving 275,000 atoms representing iron-nickel alloys in proportions found in nature. They show that transitions from one alloy structure to the other occurs in both an orderly and a disorderly way, depending on whether it is heated up or cooled down, respectively. These findings have been published in EPJ B by Emilia Sak-Saracino and Herbert Urbassek from the Research Center OPTIMAS at the University of Kaiserslautern, in Germany.


Acting EiC: Heiko Rieger

Executive Editors:
Eduardo Hernandez, Heiko Rieger, Bikas K. Chakrabarti, Wenhui Duan
I am naturally indebted to you and the referees who contributed to this success with your time and constructive advice.

Hamid Assadi

ISSN (Print Edition): 1434-6028
ISSN (Electronic Edition): 1434-6036

© EDP Sciences, Società Italiana di Fisica and Springer-Verlag

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