Actively Learning Materials Science Workshop 2023

27.2.-3.3.2023 Helsinki/Espoo, Finland

Highly concentrated participants in one of the in-depth tutorial sessions.

From 27th to 3rd March 2023 the Actively Learning Materials Science workshop was held at Aalto University in Helsinki/Espoo, Finland. This workshop welcomed 81 in-person participants from 10 countries (and many more among the 50+ online participants), also comprising 12 invited members among lecturers, teaching assistants, organizers and technical helpers. The event was sponsored jointly by CECAM, the Psi-k organization, Aalto University, and the Finnish Center for Artificial Intelligence, with talk and poster prizes sponsored by Wiley.

The workshop was dedicated to active learning (AL) algorithms, i.e. algorithms where machine learning datasets are collected on-the-fly in the search for optimal solutions. Paradigmatic examples in this area include (but are not limited to) Active Learning methods, Reinforcement Learning protocols, and Bayesian Optimization approaches. In the tutorials, talks and poster presentations, the participants showcased how AL enables to tackle outstanding problems in the optimal design of experiments, efficient traversal of complicated search spaces for electronic structure simulations and high throughput screening.

A key strength of AL techniques lies in the automated manner in which the machine learning model selects the data to include into the dataset via acquisition strategies. The requested data points can then be evaluated via computation or experiment and included into the model iteratively, until the optimal solution converges. The resulting compact, maximally informative datasets make AL particularly suitable for applications where data is scarce or data acquisition expensive. In this way, AL has helped accelerate materials discovery  away from big-data and free of human bias. Despite recent successes, future applications of AL on experimental data are slow, given that key data infrastructure is still lacking. Working with multiple objectives, or multidimensional data remains challenging. Novel method development across the research field is needed to advance AL techniques and associated frameworks in materials research.

Actively Learning Materials Science (AL4MS) focussed on two key objectives, both from a pedagogical (first part of the event) as well as from an advanced perspective (second part of the event): 1) How could data infrastructures and AL algorithm development advance experimental materials discovery? 2) How could we combine multiple channels of information in the same AL model? Continue reading Actively Learning Materials Science Workshop 2023

Workshop on quantum dissipation by swift nuclei in condensed matter

Workshop photograph at CECAM headquarters

During 7-9 December 2022 the workshop on quantum dissipation by swift nuclei took place in Lausanne, at the CECAM headquarters. It was jointly funded by CECAM , Psi-k, and the Lawrence Livermore National Laboratory. It brought together key people in the fields of electronic stopping of nuclei in matter, non-adiabatic quantum dynamics, and density-functional theory and many-electron dynamics, to face the problem of quantum dissipation of swift nuclei in matter, from quantum friction effects of ions/molecules on surfaces and nanoconfined flow, to strong dissipation under irradiation. Invited speakers were prompted to talk about their recent work and ideas in their own topics which they thought could connect to the other subfields. The general ambition was cross-fertilisation,and exploring how connections of advances in one field might contribute to the others. In the spirit of traditional Psi-k / CECAM workshops, ample opportunity for discussion and lateral collective thinking was provided.

Full details can be found in the CECAM web page for this event.

The format consisted of three full days, including seven talks and a discussion session per day, after the afternoon coffee break. Slots of 40 min were allocated per speaker, aiming at 20-25 min of lecture and 15-20 min of discussion. Most of the talks were delivered in-person, The workshop was structured in three interconnected themes, one per day, starting with nuclei as projectiles (experiment, theory, simulation), followed by levels of theory for the dynamics of the electronic subsystem, to conclude with quantum coupled dynamics of electrons and nuclei, including connection to other non-adiabatic contexts. Each day had an associated discussion session led by one of the participants who identified important open questions to be addressed in the future, as arising from the presentations.

Key needs identified and actions proposed to address them can be summarised as follows:

  1. Promoting further interactions between modelers and experimentalists and ensuring that experimentalists’ input on relevant questions and coherence between models and experimental set up is clearly disseminated. To foster this goal, the organization of a follow-up workshop driven by experimentalists was proposed and will be pursued for 2024.
  2. Clarifying and disseminating state-of-the-art and open questions via a shared publication in the form of a roadmap paper. In particular, this work should include a more important participation by the cognate community of non-adiabatic dynamics applied to chemical processes, which has developed a number of quite advanced tools, especially in the field of photochemistry.
  3. Identify challenges and benchmark systems for currently existing techniques. In particular, an adequate description of electron thermalisation after a strong energy pulse was considered a timely and suitable challenge for the dynamical simulation techniques being used (such as TDDFT).

Concluding:

It was considered a quite successful meeting by all, deserving further exploration.

Organisers:

  • Emilio Artacho (Nanogune, DIPC, Ikerbasque, U. Cambridge),
  • Sara Bonella (CECAM, EPFL),
  • Alfredo Correa (Larence Livermore National Lab)
  • Jorge Kohanoff (U Complutense, Madrid)

Conference on Defects in Solids for Quantum Technologies (DSQT2022)

From the 12th to 17th of June 2022, the conference on defects in solids for quantum technologies was held in Stockholm, Sweden, at the AlbaNova University Center of Stockholm University. The final scientific program of the conference lasted for five full days, included 34 invited talks, 48 contributed talks, and a poster session with 30 posters, all-in-all having 119 participants from 21 countries. The event was sponsored jointly by the Psi-k organization and  CECAM, and partly funded by the organizing universities of Linköping University and Stockholm University with funds from the Knut and Alice Wallenberg Foundation.

The conference covered the state-of-the-art advances in the study of defects in semiconductors and the quantum properties they exhibit which are favorable for applications in future information, communication, and sensing technology. Considerable effort has been spent to develop a basic unit of quantum information processing (or qubit) from different individual quantum systems, such as single atoms or ions trapped in a crystal lattice, single Josephson superconducting devices, single photons emitted from quantum dots or single photons/spins associated with point defects in semiconductors. Quantum states due to point defect in wide band gap semiconductors may realize single photon sources and quantum bits that can be harnessed in quantum information processing and nanoscale sensor applications at room temperature. The leading contender is the nitrogen-vacancy center in diamond that may be considered as a robust quantum bit. However, the possibility to realize bright single-photon emitters and single spin sources (single defects with spin) in SiC, Si, and hBN have been demonstrated. Researchers face many materials science challenges in fabricating point defect quantum states with favorable intrinsic properties that can be perturbed by other defects either in bulk or at the surface of the devices. First principles theoretical simulations have been demonstrated as an essential tool in understanding the underlying physics of these atomic scale systems as well as in identification of potential new quantum bits and single photon emitters in wide band gap semiconductors. Therefore, tight collaboration of experimental research and atomistic simulations is essential for a rapid progress in the field. Continue reading Conference on Defects in Solids for Quantum Technologies (DSQT2022)

Psi-k supported focus session at DPG Meeting

Frontiers of Electronic-Structure Theory @ DPG Meeting 2023

The DPG Spring Meeting of the Condensed Matter Division is the largest European physics conference (the second largest physics conference worldwide), covering all aspects of condensed matter and chemical physics, and materials science. For many years, Psi-k has supported a Focus Session on Frontiers of Electronic-Structure Theory with a special focus topic that changes from year to year.  In 2023 the focus will be on Large-scale Calculations Enabled by Sharing Developments and Tools, organised by Claudia Draxl, Andris Gulans, Xavier Gonze, and Dorothea Golze.

Abstract

Electronic-structure calculations, based on density-functional theory (DFT) and methodology beyond, are getting increasingly involved as they face the following challenges: First, investigations of modern materials typically require large unit cells, owing to complex crystal structures, mixed compositions, internal interfaces, etc. Second, at the same time, they often require advanced methods, including hybrid functionals of DFT, Green-function techniques from many-body perturbation theory (MBPT), high-level wavefunction-based methods like coupled-cluster (CC) theory, or quantum Monte-Carlo simulations. All these methods should ideally be implemented in scientific software that is running efficiently on modern supercomputers. With both methodology and computer architectures exhibiting increasing complexity, collaborative development and shared tools, including ready-to-use libraries and codes, are becoming indispensable. This interdisciplinary symposium will cover recent progress in the broad area of electron-structure methods and highly-sophisticated tools that enable the entire community to explore most exciting materials from different perspectives to either predict peculiar features or get insight into measured counterparts. The invited talks will be given by leading and emerging experts in the field. Contributed talks and posters will be from researchers working on developing methods and tools as well as applications to advanced materials.

Unfortunately, due to the venues decision not to host external events, there will not be a Psi-k Get Together this year. However, we look forward to seeing you all at the focus session and we will endeavour to include the Psi-k Get Together at next year’s meeting.

Claudia Draxl
Symposium coordinator

Peter Haynes
Chair of Psi-k

2022: Frontiers of Electronic-Structure Theory: Focus on Artificial Intelligence applied to Real Materials
2021: Electron-Phonon Interactions (postponed from 2020)
2019: The Interface Challenge
2018: Correlated Electron Materials
2017: New Concepts and Developments in Density Functional Theory and Beyond
2016: Topology and Transport
2015: Many-body Effects on the Nano-Scale
2014: Non-equilibrium Phenomena at the Nano-scale
2013: Discovery of Novel Functional Materials
2012: Strong Correlations from First Principles

TREX School on QMC with TurboRVB

We are inviting young students and more senior researchers interested in learning ab initio quantum Monte Carlo, one of the most accurate and versatile approaches for materials and electronic structure calculations, to apply for the upcoming TREX School on QMC with TurboRVB, taking place from 3-7 July 2023 in Trieste, Italy. This QMC summer school is organized by TREX project and it will be held in the Scuola Internazionale Superiore di Studi Avanzati (SISSA).

It will be a great event to learn TurboRVB (QMC algorithms), TurboGenius (command-line tools to make QMC calculations user friendly), and TurboWorkflows (high-throughput computations) codes for QMC applications and tutorials. And, this time, to meet your peers and colleagues in person.
After many years of development, the TurboRVB code will be officially released as an open source package during this school.

Why should you join the School?

  • The TREX project is offering participants free lodging, coffee breaks, lunch breaks and a social dinner during the School. This will be the perfect occasion to meet your peers and colleagues in person, share experiences and learn more about QMC methods and how to use them in practice.
  • Participants are invited to submit their poster contributions and present results and ongoing activities at the School.  The best poster winner will win a stay of one week at Sorbonne University, Paris, in the Quantum Theory of Materials group (IMPMC)
  • After many years of development, the TurboRVB code will be officially released as an open source package during this school. Do not miss this event!
  • Get the chance to explore beautiful Trieste, top-ranked in Italy for its quality of life, and to discover this town renowned for its scientific institutions. If you want to extend your stay in Trieste for one more week, the week after the school there will be a workshop organized at the ICTP about “QMC methods at work for describing novel states of matter”, a perfect follow-up of our school! Please, note that a separate registration is required for the ICTP workshop. Please, also note that the TREX project is not covering participant’s travel nor extra costs.

Important information

  • We have a limited number of seats so please consider submitting your application as soon as possible. Deadline for application is  28.05.2023 COB.
  • Attendees are supposed to have a background in condensed matter theory and/or quantum chemistry.
  • Attendees are kindly requested to bring their own laptop.
  • We invite the attendees to bring a poster with them about their own research (even if unrelated to QMC). A poster session will be organized during the school and the three best posters will be awarded. The best poster prize is a stay of one week at Sorbonne University, Paris, in the Quantum Theory of Materials group (IMPMC)

MORE INFO | PROGRAMME | REGISTRATION | VENUE

Psi-k Working Groups

Dear all

Our working groups are the heart of the Psi-k community, and the Board of Trustees wishes to express its thanks to the leaders and members of the current groups for serving us in these roles.

Following on from the presentation and discussion at the Annual Community Meeting in December, the Board of Trustees has now approved the titles and scopes of the new working groups. These can be found on the Psi-k web site.

We now need to select members and a leader for each working group in time for them to participate in the review of outline workshop proposals in July. Their roles and responsibilities are also detailed on the web page above. Other key tasks for these new groups will be to assist in the planning of the scientific programme for the next Psi-k Conference in 2025 and the shortlisting of nominations for Psi-k awards.

Psi-k is committed to promoting equality, diversity and inclusion at all levels, paying particular attention to:

  • gender balance;
  • spread across career stages;
  • geographical representation.

In particular, it has been agreed that each working group will include one member who is an early career researcher* and one member from outside Europe.

The current working groups were established in 2018 with the expectation that they would be refreshed at the following Conference. The expectation now is that leaders who have served for five years will normally stand down from this role, but that they may be nominated to stay on as members to provide continuity. Current members who have been particularly active may also be nominated to continue. It is anticipated that around half of the membership of the new working groups will be taking on this role for the first time.

Individuals may self-nominate, but the Board of Trustees is particularly keen to seek nominations of individuals who may be reluctant to put themselves forward, especially those working in eastern Europe or from under-represented groups within our community. We urge senior members of the Psi-k community to consider carefully whom they might nominate.

Nominations should be submitted via this Google form. There is no formal deadline, with nominations being considered as they are received, but the trustees will begin inviting new members from the middle of April. You are welcome to submit more than one nomination.

Best wishes,

Peter Haynes
Psi-k Chair of Trustees

*An early career researcher is someone holding a PhD but who does not yet hold a permanent position within a university, research institute or company.

TREX workshop on electronic structure methods for strong correlation: theory, computational algorithms, and codes

TREX project is inviting  advanced PhD students and post-docs to join the “TREX workshop on electronic structure methods for strong correlation: theory, computational algorithms, and codes” which will be held on 18-20 April 2023 at the nstitute of Physics, Lodz University of Technology, Poland.

The primary purpose of the workshop is to provide insight into both theory and computer implementation of electronic structure methods dedicated to strongly correlated materials.

The workshop provides a unique opportunity to learn theories behind  electronic structure methods for strongly correlated materials and to get insight into their computer implementation in open-source TREX flagship codes:

Each workshop session will consist of lectures and tutorials. Lectures will present theoretical backgrounds of the covered methods and numerical algorithms used in their computer implementation. Tutorial sessions, led by code developers, will provide participants with hands-on experience on using codes, paying special attention to high performance computing.

A separate session will cover application of machine learning to predicting molecular properties.

Participants

The workshop is open to all participants. Lectures will have a didactic character and we strongly encourage advanced PhD students and post-docs to participate.

Requirements

Basis knowledge of ab initio electronic structure methods is required.

Fee

There is no registration fee. Free lodging in the university guest house will be provided to a limited number of participants, based on the first-come, first-serve basis (early registration is encouraged). Lunches are provided to all participants.

REGISTRATION  | PROGRAMME | EVENT COMMITTE | VENUE

 

SCIENTIFIC REPORT ON THE “21ST INTERNATIONAL WORKSHOP ON COMPUTATIONAL PHYSICS AND MATERIALS SCIENCE: TOTAL ENERGY AND FORCE METHODS”

21th Total Energy Workshop, ICTP, Trieste (Italy), 11-13 January 2023

The “Total Energy” Workshop is held traditionally in Trieste every two years, since 1987. It is devoted to recent advances in computational condensed matter physics and materials science, based on realistic calculations of the electronic structure of complex systems. It has become one of the most popular regular events of the international ab-initio electronic-structure community. The 2023 edition confirmed this tradition, with a large number of participants, lively discussions and, furthermore, with a large number of contributed posters. Overview, speakers list, program with the relevant material (Conference Book, abstracts, list of attendees,…) are available on the web page:

https://indico.ictp.it/event/10056/ Continue reading

Computational modelling of batteries: First-principles quantum chemistry meets continuum approaches

Computational modelling of batteries:
First-principles quantum chemistry meets continuum approaches
Castle Reisensburg near Ulm/Germany
October 23 – 26, 2022

Description of the Event

Due to the importance of electrochemical energy storage for our future sustainable supply of energy, worldwide there are constantly increasing research and development activities with respect to secondary, i.e. rechargeable batteries. Still, due to the complexity of batteries, our fundamental understanding of structures and processes in batteries is to large extent still rather limited. In many areas of science, theoretical and computational modelling plays an increasingly important role, also in the field of battery research. Hence, a close collaboration between experimental and theoretical researchers can be very beneficial. However, from a theoretical and computational point of view, the modelling of batteries is rather challenging due to the complexity of the structures and processes present in the anode, electrolyte, and cathode of batteries and at their interfaces.

In addition, the relevant processes in batteries occur at a wide range of length and time scales, from the nanometer and picosecond scale with respect to the elementary atomic processes upon charge and discharge up to the centimeter and year scale with respect to the operation of batteries and aging and degradation processes. The modelling of structures and processes at these vastly different scales requires rather different theoretical and numerical methods, from quantum chemistry methods on the atomic scale to continuum models on the macroscopic scale. Still, the processes at the different scales are strongly interrelated. For example, any long-term degradation process is initiated and thus based on chemical processes on the atomic scale.

Unfortunately, the scientific communities performing battery modelling at the atomistic and the macroscopic length scale are rather disjunct. Hence it was the goal of the workshop on “Computational modelling of batteries: First-principles quantum chemistry meets continuum approaches” at Castle Reisensburg near Ulm from October 23 to 26, 2022, to bring together world-leading experts of both communities. The first aim was to foster the exchange between the two communities to create an awareness of the theoretical and numerical challenges of the other field. Secondly and almost more importantly, the workshop was intended to inspire collaborations between researchers of both communities in order to allow a holistic theoretical and numerical description of structures and processes from the atomistic to the macroscopic scale.

This workshop was organized by Axel Groß of Ulm University and Arnulf Latz of the Helmholtz Institute Ulm for Electrochemical Energy Storage. Both are also PIs at the Cluster of Excellence POLiS – Post-Li Storage. This workshop was generously supported by the German Science Foundation (DFG), the Cluster of Excellence POLiS, and by the Psi-k Network for electronic structure calculations of complex processes in materials. Continue reading Computational modelling of batteries: First-principles quantum chemistry meets continuum approaches

Ab initio (from electronic structure) calculation of complex processes in materials