Washington, Mulhouse, Trieste, 29 August 2022 -- The American Physical Society (APS), the European Physical Society (EPS) and the International Centre for Theoretical Physics (UNESCO-ICTP), in honour of the International Year of Basic Science for Sustainable Development (IYBSSD 2022), announce the initiation of the joint APS-ICTP-EPS Travel Award Fellowship Programme (ATAP). ATAP is aimed at active early career scientists from developing countries, supporting short-term research visits to laboratories in Europe and North America.

This programme grants the major costs of two-month visits for young scientists, up to $5,000. Applicants just need to send their complete CV including publications, at least one letter of reference, a letter of agreement and endorsement from the host laboratory and a 1-page budget management plan evaluating the travel and local expenses. The materials must be sent to itlabs@ictp.it by 28 February in the year of the intended Fellowship.

The goal of ATAP is to enable selected recipients to strengthen opportunities to conduct world-class research, and establish collaborations to enhance their scientific careers. The recipients may return to the laboratories of their alma mater to use laboratory facilities they are familiar with and re-connect with colleagues.

We are happy to announce the selected recipients of the 2022 ATAP programme:

Dr. Azam KARDAN, Damghan University, Iran, who will spend two months at the MAX IV Laboratory of Lund University, Sweden, to work with Profs. Martin Bech and Pablo Villanueva Perez on tomographic acquisitions using machine learning;

Dr. Llinersy URANGA PINA, University of Havana, Cuba, going to the University Paul Sabatier in Toulouse, France, where she will work with Prof. Dr. Christoph Meier and Dr. Nadine Halberstadt on materials science;

Dr. Ausama Ismael KHUDIAR, Institute of Materials Research/Department of Sciences and Technology of the Ministry of Higher Education and Scientific Research, Republic of Iraq, who will go to the Eberhard Karls Universität in Tübingen, Germany, to work with Dr. Nicolae Barsan on gas sensors.

Author: Gina Gunaratnam

On 2^nd December 2021, the United Nations declared 2022 the International Year of Basic Sciences for Sustainable Development (IYBSSD2022). The resolution is the result of a proposal from the IUPAP (International Union of Pure and Applied Physics) led by Michel Spiro, its current president, in coordination with international scientific organisations such as CERN, EGO, IAU, SKA Observatory, to name but a few (list of organisers).

With this Year, the United Nations General Assembly  « invites all [its] Member States, organizations of the United Nations system and other global, regional and subregional organizations, as well as other relevant stakeholders, including academia, civil society, inter alia, international and national non- governmental organizations, individuals and the private sector, to observe and raise awareness of the importance of basic sciences for sustainable development, in accordance with national priorities».

The European Physical Society (EPS) is a founding partner and a member of the Steering Committee of the IYBSSD2022. The EPS strongly supports this initiative as it encourages the dissemination of basic sciences through its involvement in related European projects and programmes.

The « Joint APS-ICTP-EPS Travel Award Fellowship Programme » is an example of activities that will start in 2022, where the EPS is involved together with the APS (American Physical Society) and the ICTP (Abdus Salam International Centre of Theoretical Physics). This programme enables early career scientists to return to universities and research centres where they had previously obtained their PhD, to use laboratory facilities which may not be available in their home country and to gain training on writing grant proposals, among others.

The EPS will program more activities in the frame of the IYBSSD2022, that will officially be inaugurated on 30 June-1st July 2022 with a conference held at the UNESCO headquarters in Paris. Check our website for the latest news.

For more info :

• Press release of the United Nations
• IYBSSD2022 website
• social media: @IYBSSD2022 and #IYBSSD2022
• Joint APS-ICTP-EPS Travel Award Fellowship Programme 
• EPS website

On 10th May, 2022, the old Physics Department of Lund University, Sweden, was inaugurated as an EPS Historic Site. The building, which is located at Biskopsgatan 3, Lund, served the Lund physicists during the years 1885 to 1950. It had two halls for instruments, an auditorium, 12 offices, a library and a workshop. The building then became the base for classical studies (Classicum) until in 2009 after renovation became the site of the interdisciplinary Pufendorf Institute of Advanced Studies. The ceremony was actually planned for 26th May 2020, but had on short notice to be moved forward due to the Covid-19 pandemic.

The nomination as an EPS Historic Site is based on the work of Johannes (Janne) Rydberg (1854-1919), who was active in analyzing atomic spectral lines, which Bunsen and Kirchhoff around 1850 had found to be specific for each species. Balmer had in 1885 found a formula to describe the lines of hydrogen. Being an excellent mathematician, with a great feeling for numbers, Rydberg found a more general formula, which also worked well, e.g. for the alkali atoms. He presented his first results in 1887 in a report to the Royal Swedish Academy of Sciences, and more in detail in a presentation to the Mathematical-Physical Society in Lund in 1888. The full account of his findings occurs in a scientific article published in German in 1890 (Zeitschrift für Physikalische Chemie). The most amazing aspect of this formula was that there occurred a constant, which was the same for all elements and all spectral series. In his early model for the atomic structure, Niels Bohr could in 1913 also give a theoretical value for the constant, which well agreed with the experimental value found by Rydberg. The constant came to be known as the Rydberg constant, and is presently determined to an extremely high precision using laser spectroscopy. Rydberg´s name is also associated with the much studied Rydberg atoms, which are very highly excited atoms becoming accessible through laser spectroscopy, and through the Rydberg-Ritz combination principle of atomic spectroscopy.

It can be noted that Manne Siegbahn (1886-1978) was also active in the building, making ground-breaking precision X-ray spectroscopy studies. Bengt Edlén (1906-1993), who in 1941 solved the old problem of the origin of the corona lines from the sun, was a further prominent Lund atomic physicist.

The inauguration ceremony was organized and led by Sune Svanberg, who had also made the site nomination. Stacey Ristinmaa Sörensen, the Pufendorf Institute director, welcomed a large crowd of fellow physicists assembled to celebrate, and Joachim Schnadt, chairman of the Department of Physics, recalled the work by Rydberg. Mats Helmfrid expressed his appreciation on behalf of the Lund City Council. The chairman of the EPS selection committee for historic sites, Karl Grandin, introduced the EPS programme together with the EPS president, Luc Bergé, who also performed the solemn uncovering of the memorial plaque, accompanied by a brass band.

A Rydberg Lecture, in a series of named lectures sponsored by the Royal Academy of Science, followed at the new Physics Department directly after the inauguration ceremony. The speaker was Jun Ye, JILA, National Institute of Standards and Technology and University of Colorado, who in his talk “Tick Atoms in Unison” described how extremely accurate atomic clocks could be influenced by the gravitational shift due to only one mm of vertical clock movement.

A Rydberg dinner arranged with some 30 guests in the recognized building, with speeches including by the Lund University vice Chancellor, Erik Renström, concluded a memorable day.

The memorial plaque at the old Physics Department, Lund University, has just been uncovered.
FLTR: Sune Svanberg, Lund Laser Centre, Karl Grandin, Chair of the EPS Historic Sites Selection Committee,
Luc Bergé, EPS President, Joachim Schnadt, Department of Physics, and Mats Helmfrid, Lund City Council

Photos: Sune Svanberg & Katarina Svanberg

An international research team, led by DIPC and Princeton University, discovered that almost all materials in nature exhibit at least one topological state, contradicting the 40-year-old assumption that topological materials are rare and esoteric. In a paper published this week in Science, the team also introduces the new concept of “supertopological” to the theory of band topology.

For the past century, students of chemistry, materials science, and physics have been taught to model solid-state materials by considering their chemical composition, the number and location of their electrons, and lastly, the role of more complicated interactions. However, an international team of scientists from the Donostia International Physics Center (DIPC), Princeton University, the University of Basque Country (UPV/EHU), the Max Planck Institute, l’Ecole Normale Supérieure, the CNRS, and MIT has recently discovered that an additional ingredient must also be equally considered - the notion of topology for every electronic band.

First codified in the 1980s by Michael Berry, Joshua Zak, and S. Pancharatnam, band topology is a physical property of some materials distinguished by unusually robust states, making the electronic properties of their exposed surfaces and edges insensitive to local perturbation. Topological phases of matter in 3D materials were first discovered 15 years ago by researchers including Andrei Bernevig, a member of the research team. Topological materials have been proposed as venues for observing and engineering exotic effects, including the interconversion of electrical current and electron spin, the tabletop simulating exotic theories from high-energy physics, and even, under the right conditions, the storage and manipulation of quantum information. Though a handful of topological materials have been uncovered through chemical intuition, topological electronic states in solid-state materials were generally considered to be rare and esoteric.

However, using high-throughput computational modeling, the team discovered that over half of the known 3D materials in nature are topological. As reported today in Science, the team performed complete high-throughput first-principles calculations searching for topological states throughout the electronic structures of all of the 96,196 recorded crystals in the Inorganic Crystal Structural Database, an established international repository for reporting experimentally studied materials. As stressed by Nicolas Regnault, from Princeton University and the Ecole Normale Supérieure Paris, CNRS, “this was a daunting task that took more than 25 million hours of computing time.”

Through a combined chemical and topological analysis, the team grouped the electronic structures into roughly 38,000 unique materials. The team’s data have been made freely available through a massive overhaul of the publicly accessible Topological Materials Database (https://www.topologicalquantumchemistry.com), representing a culmination of the team’s efforts over the past 6 years developing the modern position-space theory of band topology known as “Topological Quantum Chemistry.”

The team also surprisingly discovered that almost all materials - nearly 90% - host topological electronic states away from their intrinsic numbers of electrons, known as the Fermi level. Even though these states lie dormant in many experimental probes, they are still straightforwardly accessible through techniques including chemical doping, electrostatic gating, hydrostatic pressure, and photoexcitation spectroscopy. 

Supertopological materials

Perhaps more surprising than finding topological properties in almost every material, was the discovery of some extreme cases of topology across the entire energy spectrum. “Looking at our data, we amazingly saw materials with topological properties everywhere!,” exclaimed Maia Garcia-Vergniory from the Donostia International Physics Center (DIPC) and the Max Planck Institute for Chemical Physics of Solids. The team found that 2% of known materials are “supertopological,” in that every electronic band above the tightly-bound core electrons was topological. Among the materials with overlooked supertopology was bismuth, one of the most historically well-studied solid-state materials. “Our results indicate that topology is a fundamental property of matter thus far overlooked,” concluded García-Vergniory.

The ubiquity of topological features observed in numerical simulations lead to a natural question: if the results were to be believed, experimental signatures of topological states should have already been observed in earlier investigations of many materials. Combing through data from earlier photoemission experiments, the team indeed discovered this to be the case. For example, in experimental studies of Bi₂Mg₃ performed 4 years ago, the authors observed unexplained “surface resonances,” which were recognized in the current study to be overlooked topological surface states away from the Fermi level. “The evidence had always been there. We now have a concrete key towards decoding all of the surface features in spectroscopic material experiments,” noted Benjamin Wieder, a postdoctoral researcher at MIT.  “Our database is such a powerful and convenient tool,” added Claudia Felser from the Max Planck Institute for Chemical Physics of Solids. “If I am interested in a topological property, the database instantly tells me the best candidates. Then I just grow the samples in my lab, no more guesswork,” explains Felser.

“Revisiting previous experiments with a new perspective is an amazing first step,” says Andrei Bernevig from Princeton University and an Ikerbasque visiting professor at the Donostia International Physics Center (DIPC). “But we can look to an even more exciting future, in which materials with advanced functionality are designed through a marriage of human intuition and artificial intelligence, built on the foundation of the Topological Materials Database and Topological Quantum Chemistry,” concludes Bernevig.

An artistic interpretation of “Topology is everywhere”. Mobius strips are visible from all angles of the cube above,
representing the ubiquity of topological phases in solid-state materials. © C. Pouss.

Publication reference

All topological bands of all nonmagnetic stoichiometric materials

M. G. Vergniory, B. J. Wieder, L. Elcoro, S. S. P. Parkin, C. Felser, B. A. Bernevig, and N. Regnault

Science 376, eabg9094 (2022). DOI: 10.1126/science.abg9094

The International Year of Basic Sciences for Sustainable Development (IYBSSD 2022) will start on 23rd June 2022 at the headquarters of UNESCO in Paris. The European Physical Society is a partner of IYBSSD 2022 and supports this international year throught its involvement in several projects described below.

APS-ICTP-EPS Travel Award Fellowship Programme
The Memorandum of Understanding for the implementation of the APS-ICTP-EPS Travel Award Fellowship Programme has been signed. It will begin in 2022 as part of the activities of the APS, ICTP and EPS for the International Year of Basic Sciences for Sustainable Development. EPS Divisions and Groups and Member Societies will be asked to advertise the programme, and to identify suitable candidates.
https://www.ictp.it/programmes/career-development/aps-ictp-eps-travel-award-fellowship-programme.aspx

11th Balkan Physical Union General Conference
The EPS has agreed to support the organisation of the 11th Balkan Physical Union General Conference which will take place in Belgrade (HR) from 28th August to 1st September 2022.
https://bpu11.info/

UFPLP Conference
The União dos Físicos de Países de Língua Portuguesa (UFPLP, union of Portuguese-speaking countries) organises the UFPLP Conference, which will take place from 12th-16th September 2022 in Cape Verde and have for central theme « Physics for sustainable development ».
https://4cfplp.sci-meet.net/pt

Migrations Co-dévelopement Alsace (MCDA)
Support for a conference on water and the environment, organised by the association MCDA, the Alsace-Morocco Co-development Association. The goal is to raise awareness among a broad audience about the need of providing drinking water to villages in Morocco lacking water.
http://mcda-asso.org/