We are glad to let you know that our esteemed colleagues Davide Donadio and Saghamitra Neogi from Max Planck Institute for Polymer Research have been appointed recently Assistant Professor at University of California Davis and University of Colorado Boulder respectively.
Davide Donadio joined the Department of Chemistry starting July 1.He has started a research program in computational materials chemistry, with particular emphasis on non-equilibrium and transport processes, and nanophononics, to enable intelligent design of new systems with desired functionalities. His research currently focuses on (bio-)templated growth and assembly of nanostructures and hierarchical materials, reactions at interfaces and in solution, nano-phononics and thermoelectric materials, and thermal transport in hybrid nanostructures and at hard/soft matter interfaces.
Sanghamitra Neogi joined the Department of Aerospace Engineering Sciences starting August 17. Her work focusses on structure-processing-property relationships in materials and structures with emphasis on vibrations, waves (kHz-THz) and heat propagation across bulk structures and interfaces, and dissipative and nonlinear dynamics. She uses an analytical theory and computational materials science approach such as classical and ab initio molecular dynamics simulations, as well as multiscale methods in her research.
We wish them success in their new positions and hope to keep a strong collaboration in the future!
Next 30 Sept. to 2 Oct. 2015 will be held in Mainz (Germany) a CECAM workshop on "Hot nanostructures: thermal transport and radiation at the nanoscale". The event is organised by MERGING researchers Prof. Davide Donadio, Prof. Olivier Bourgeois and Prof. Clivia Sotomayor Torres, together with Dr Yann Chalopin. The list of invited speakers can be found on the website and registration made online: merging.eu/hot-nanostructures.
The scope of this workshop is to gather physicists, chemists and engineers across different communities involved to various extents in the topic of thermal transport and radiation at the nanoscale, to favour the exchange of ideas and plant the seed for future collaborations, which would benefit from a broad and diversified background.
We plan to involve scientists working on the fundamentals of statistical physics and heat transport in low dimensional systems, theoretical material scientists involved in simulations, experimentalists measuring phonon transport in nanostructures, in nanocomposites and heat exchange between nanoparticles and soft matter, and engineers designing new materials and devices for thermal management and energy conversion.
The workshop will focus on the following main topics:
- statistical physics and foundations of heat transport in low dimensional systems
- design of efficient thermoelectric materials for energy harvesting, active cooling metrology
- fundamentals of radiation at the nanoscale: optical properties and near field
- transport and radiation in soft and biological systems
Such topics will be subject of lectures from the invited speakers and will be developed into four topical round-table discussions, and in a final debate on the future perspectives of the field of nanophononics and nanoscale heat transfer.
This choice of topics should provide a fair balance between fundamental science and applications. As for fundamental principles of heat transfer at the nanoscale, it will be useful to compare and match the models and interpretations of experimentalists and engineers, with those of statistical physicists and computational materials scientists, finding a correspondence between a mesoscopic understanding of phonon transport and atomistic simulations.
A major effort will be deployed in moving the field beyond traditional applications of phononic engineering, such as improving the performances of thermoelectric materials, towards exploring the perspectives of innovative applications, related for example to medical treatments and imaging or phonon-based information technology.
Download the flyer.
Come and discover the latest achievements of the MERGING project at Phonons 2015 from 12 to 17 July in Notthingham, UK. Members of ICN2, CNRS, CEA and MPIP will present their latest results in phononics at the nanoscale.
Yanqing Liu will talk about "Significant reduction of thermal conductivity in a nanostructured semiconductor single crystal" during Tuesday afternoon session on "Phonon transport". Francesc Alzina will talk about "Silicon nano-membrane-based phononics" during Tuesday afternoon session on "Phononic crystals".
Looking forward to see you there!
Come and discover the latest achievements of the MERGING project at Phononics 2015 from May 31 to June 5 in Paris, France. Members of ICN2, CNRS, CEA and MPIP will present their latest results in phononics at the nanoscale.
Sanghamitra Neogi and Yanqing Liu will talk about "Phononic thermal transport in nanostructured ultra-thin silicon membranes" and "Significant reduction of thermal conductivity in a nanostructured semiconductor single crystal" respectively during afternoon session 2 on Monday 1 June.
Bartlomiej Graczykowski will talk about "Brillouin spectroscopy of silicon-based phononic crystal" during afternoon session 2 on Tuesday 2 June.
Looking forward to see you there!
22nd April 2015. The ability of materials to conduct heat is a concept that we are all familiar with from everyday life. The modern story of thermal transport dates back to 1822 when the brilliant French physicist Jean-Baptiste Joseph Fourier published his book “Théorie analytique de la chaleur” (The Analytic Theory of Heat), which became a corner stone of heat transport. He pointed out that the thermal conductivity, i.e., ratio of the heat flux to the temperature gradient is an intrinsic property of the material itself.
The advent of nanotechnology, where the rules of classical physics gradually fail as the dimensions shrink, is challenging Fourier's theory of heat in several ways. A paper published in ACS Nano and led by researchers from the Max Planck Institute for Polymer Research (Germany), the Catalan Institute of Nanoscience and Nanotechnology (ICN2) at the campus of the Universitat Autònoma de Barcelona (UAB) (Spain) and the VTT Technical Research Centre of Finland (Finland) describes how the nanometre-scale topology and the chemical composition of the surface control the thermal conductivity of ultrathin silicon membranes. The work was funded by the European Project Membrane-based phonon engineering for energy harvesting (MERGING).
The results show that the thermal conductivity of silicon membranes thinner than 10 nm is 25 times lower than that of bulk crystalline silicon and is controlled to a large extent by the structure and the chemical composition of their surface. Combining state-of-the-art realistic atomistic modelling, sophisticated fabrication techniques, new measurement approaches and state-of-the-art parameter-free modelling, researchers unravelled the role of surface oxidation in determining the scattering of quantized lattice vibrations (phonons), which are the main heat carriers in silicon.
Both experiments and modelling showed that removing the native oxide improves the thermal conductivity of silicon nanostructures by almost a factor of two, while successive partial re-oxidation lowers it again. Large-scale molecular dynamics simulations with up to 1,000,000 atoms allowed the researchers to quantify the relative contributions to the reduction of the thermal conductivity arising from the presence of native SiO2 and from the dimensionality reduction evaluated for a model with perfectly specular surfaces.
Silicon is the material of choice for almost all electronic-related applications, where characteristic dimensions below 10 nm have been reached, e.g. in FinFET transistors, and heat dissipation control becomes essential for their optimum performance. While the lowering of thermal conductivity induced by oxide layers is detrimental to heat spread in nanoelectronic devices, it will turn useful for thermoelectric energy harvesting, where efficiency relies on avoiding heat exchange across the active part of the device.
The chemical nature of surfaces, therefore, emerges as a new key parameter for improving the performance of Si-based electronic and thermoelectric nanodevices, as well as of that of nanomechanical resonators (NEMS). This work opens new possibilities for novel thermal experiments and designs directed to manipulate heat at such scales.
Sanghamitra Neogi, J. Sebastian Reparaz, Luiz Felipe C. Pereira, Bartlomiej Graczykowski, Markus R. Wagner, Marianna Sledzinska, Andrey Shchepetov, Mika Prunnila, Jouni Ahopelto, Clivia M. Sotomayor-Torres, and Davide Donadio. Tuning Thermal Transport in Ultrathin Silicon Membranes by Surface Nanoscale Engineering. ACS Nano, 9 (4) 3820-3828 (2015). Publication Date (Web): March 31, 2015.
Futurium is the online platform launched by the European Commission to facilitate a broad reflection on future European policies.
Launched by the Directorate General for Communications Networks, Content and Technology of the European Commission it aims to facilitate a broad reflection on future European policies. It combines the informal character of social networks with the methodological approach of foresights to engage stakeholders in the co-creation of futures and policy ideas that matter to them.
Recently this platform interviewed ICREA Professor Clivia Sotomayor, leader of the ICN2 Phononic and Photonic Nanostructures Group (P2N). She described how the future will develop for in the field of nanophononics applied to semiconductors. In particular, she emphasized the applications in the energy and information processing sectors. She also introduced the main challenges of the field and explained how policies could help in overcoming them. The project MERGING is a good example of how advances in the control of phonons can lead to useful applications and a benefit for the society.
Listen to the podcast
Read a summary of the interview
Prof. Clivia M. Sotomayor Torres, coordinator of the MERGING project, is coorganiser of MRS 2015 symp. M on Nanoscale Heat Transport─From Fundamentals to Devices together with Prof. Jonathan A. Malen, Prof. Eric Pop and Prof. Woochul Kim. The symposium will tackle topics ranging from thermal conductance of a broad range of systems to heat transport in materials and devices for thermoelectric energy conversion and from heat flow in micro-electronic, -fluidic, and -mechanical and biosensing devices to electron-phonon and phonon-phonon interactions.
The 2015 MRS Spring Meeting will be held in San Francisco from 6 to 10 April 2015.
More information can be found here.
Three members of the MERGING consortium - Prof. Jouni Ahopelto, Prof. Davide Donadio and Prof. Clivia M. Sotomayor Torres - have been invited as keynote speakers at IMAGINANO 2015 in Bilbao, Spain. They will present the latest advances in nanophononics in relation with the MERGING project. IMAGINANO is the largest European event in nanotechnology. This year it will gather six different conferences and the main focus will be on Nanoscience & Nanotechnology in the fields of Graphene, Bio/Medicine, Optics, Photonics, Chemistry, Toxicology.
More information: http://www.imaginenano.com/SCIENCE/Scienceconferences_PPM2015.php.
The position is at the Department of Materials and Nanophysics of the KTH Information and Communication Technology. KTH (www.KTH.se) is a leading research and teaching institution in Europe. The position is tenable at the Department of Materials and Nanophysics of the KTH Information and Communication Technology.
The successful candidate will become responsible for the day-to-day work of the project “Heat transport in III‐V semiconductors: phonon engineering for thermal management”, which includes sample design, growth specifications, structural electrical and optical characterisation, thermal studies and modelling, documentation and publications. She or he is expected to carry out publishable research in the general field of phononics.
The EUPHONON position paper on nano-phononics has been released. It is one of the main outputs of the EUPHONON coordination action (www.euphonon.eu), a EU project which mission was to build a European community for nano-phononics. The document aims at defining nano-phononics, bringing forth the urgent need to aggregate a nano-phononics community in Europe and boost its consolidation. This report seeks to demonstrate that phonons are at the conceptual heart of several scientific communities such as the Terahertz Phonons, Micro/Nanoscale Heat Transfer like in MERGING, Nanomechanics and Optomechanics, Thermodynamics and Statistical Physics communities.
Expected impact of initiatives such as this position paper is to enhance visibility, communication and networking between specialists in several fields, facilitate rapid information flow, look for areas of common ground between different technologies and therefore shape and consolidate the Nanophononics European research community.
The main recommendation concerns the implementation of essential actions in the form of, e.g., a FET pro-active initiative in Nanophononics would energise and galvanise the active collaborations to put forward outstanding research concepts to position Europe in an undoubted leadership position in this field, which underpins future communication technologies. Additionally, the communities need more time to gather and consolidate. The current EUPHONON project has made an excellent start but a fresh initiative, including industry, is a condition for longlasting impact. Finally, intense networking with Chinese and American colleagues through bilateral research projects, joint workshops and research exchanges should be seriously considered.
The whole position paper has been published in e-nanonewsletter (issue num. 30) and can be downloaded here.
On Wednesday 28th May 2014 Miss Yanqing Liu, Ph.D. student at the CNRS Institut Néel, received the best student presentation award of the E-MRS symposium D on "Phonon and Fluctuations in Low Dimensional Structures". Her presentation, entitled "Nanostructured GeMn thin film: an efficient thermoelectric material", focussed on germanium-based material as highly promising thermoelectrics, along with the advanced experimental techniques developed for the characterization of its thermal properties. The MERGING partners would like to say CONGRATULATIONS!
The whole MERGING consortium met in Lyon (France) on 8th and 9th May 2014. This was the opportunity to present the latest achievements and plan the future work. Intense scientific and technical discussions were conducted during the two-day meeting leading to fruitful agreements and challenging ideas.
Dr Claudia Mangold and Dr Davide Donadio from Max Planck Institute for Polymer research have received a computer time award of 10 million hours at the Gauss Center for Supercomputing GCS for the project "Membrane-based phonon engineering for energy harvesting: characterisation of Mn-Ge". This is a great chance for them to boost calculations and simulations for the MERGING project.
The first symposium dedicated to phonon effects at the nanoscale within the E-MRS conference will take place in Lille (France) from 26th to 29th May 2014. This symposium is co-organised by MERGING members Prof Dr Clivia M Sotomayor Torres and Prof Dr Jouni Ahopelto, together with Prof Dr Sebastian Volz.
The symposium will focus on the transfer of energy across atomic interfaces and the propagation of energy in the nm-scale. The objective is to bring together concepts from solid state and statistical physics to converge towards a comprehensive understanding of coherence, energy-temperature in the nm-scale, chaos and noise phenomena. Some of the hot topics covered by the symposium and directly linked to the research activity of MERGING include:
- Radiative heat transfer
- Energy Conversion in the Nano scale
- Nano scale thermal conductivity
- Micro to Nanoscale thermal management
- Phononic crystals
- Photon-phonon interactions
- Coherent acoustic phonons and Phonon sources
The first year of the project was very richful in terms of disssemination of the MERGING project outputs. Members participated to over 13 conferences and workshops presenting more than 30 oral and poster works. It is worth mentioning that 13 of these presentations were invited communications at some of the major international events in the field of material science and thermal management such as the 2013 editions of the MRS and Imaginano. Let's keep working hard to achieve a similar recognition from our peers in 2014.
On Monday 25th November 2013, almost coinciding with the completion of the first year of the MERGING project, 20 members met in Barcelona to present and discuss the latest achievements and plan future actions. The meeting was really intense scientifically speaking and participants rose many ideas. The following day members of CNRS and MPG sized the opportunity to visit the ICN laboratories and discuss collaborations.
The MERGING project will be launched on the 21st and 22nd of January 2013 in Mainz, Germany. The consortium, coordinated by ICN group leader and ICREA Professor Clivia Sotomayor Torres, will meet at the Max Planck Insitute for Polymer Research to discuss and agree on an in-depth research work plan to achieve the proposed objectives. For the occasion, European Commission Project Officer Carlos Saraiva Martins will attend the event.
MERGING - Membrane-based phonon engineering for energy harvesting - is a 3-year project funded by the European Commission that will run from January 2013 until December 2015. It gathers five research institutes and one SME, namely the Catalan Institute of Nanotechnology - acting as coordinator, the French CEA and CNRS, VTT technical research centre for Finland, the Max Planck Institute for Polymer Research, and Cidete Ingenieros SL.