Warszawska Szkoła Doktorska Nauk Ścisłych i BioMedycznych

Sekretariat:

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SPOTLIGHT TALK – 25/06/2024

The Warsaw Doctoral School in Natural and Biomedical Sciences and
the Institute of Physics PAS cordially invites you to a SPOTLIGHT TALK.

The talk is given by Dr. Sérgio Nuno Canteiro de Magalhães (IPFN, Instituto de Plasmas e Fusão Nuclear, Campus Tecnológico e Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, 2695-066 Bobadela LRS, Portugal).

When and where?

25th June 2024, 10:30 am
at the IP PAS Auditorium, duration: 45 min + question time

Abstract

Recent progress in the growth techniques makes it possible to fabricate low-dimensional structures, e.g., thin films (planar multilayers), mesoscopic structures and nanostructures (lateral surface and multilayer gratings, quantum wires and dots). The opto- and micro-electronics are among the fields where the resulting novel properties of homo(hetero)-epitaxial growth of semiconductors are more significant. The optimization of the fabrication process and the physical understanding of the samples requires non-destructive structural studies of the materials. Improving the properties of the as-grown quantum materials is also fundamental from the point of view of the Nanotechnology. An example of controlled process to change the properties of materials is the ex-situ incorporation of ion species. The possibility to control dopant concentrations, depth profiling and the high purity through mass selection turn ion implantation into a silicon industry ready-to-use tool. However, the stochastic nature of the process in which energetic ions collide and penetrate the semiconductor, results in lattice damage. Although the crystal degradation is partially reversed after thermal or pressure annealing’s, vacancies and point defects introduced and rearranged after annealing create a strain field which does not disappear completely. Complementary to the direct local probing methods (atomic force microscopy, transmission electron microscopy (TEM), high angle annular dark field (HAADF) or phase analysis to determine the strain in quantum materials), the X-ray elastic scattering methods probe locally the reciprocal space, thus providing relevant information about the statistical properties of the structural parameters averaged over a large volume of a sample. X-ray diffraction (XRD) and reflectivity (XRR) in the specular and non-specular geometries are relevant techniques for these structural studies of both crystalline and amorphous systems. They are highly sensitive to the distribution of the lattice parameters (diffraction) and refractive index (reflectivity). This presentation explores the synergy between ion beam implantation and X-ray scattering techniques to advance the understanding of implanted crystalline materials. Several examples of implanted single and polycrystalline crystals will be presented following by an overview of the required theoretical principles underlying both techniques. To predict the decrease of the crystalline induced by the ion implantation, a new approach to the interpretation of the diffraction data of implanted crystals will be presented. The novel methodology considers the effects of the variations of the atom’s positions in the lattice instead of employing the static Debye-Waller, strictly related to thermal vibrations. The new method, supported by preliminary molecular dynamics simulations, is tentatively applied to chromium implanted Ga2O3 and carbon implanted 4H-SiC bulk-crystals and to argon implanted GaN thick layers grown by MOCVD on sapphire-c substrates. Finally, a brief description of the MROX software, acronym for Multiple Reflection Optimization package for X-ray scattering used to simulate the XRD data, is highlighted.

This event is supported by the Polish National Agency for Academic Exchange,
grant no.  BPI/STE/2021/1/00034/U/00001
.

About the speaker

Sérgio Nuno Canteiro de Magalhães (ORCID number: 0000-0002-5858-549X; Web of Science ResearcherID: A-6709-2018) is a DL57 researcher under the 16/IPFN contract at Instituto Superior Técnico in Lisbon, Portugal. This contract was awarded for the development of models aimed at studying the effects of ion-implanted nano-materials using X-rays and ion beams.

Sérgio Magalhães’s journey into the realm of crystal growth began with the exploration of recent advancements in techniques, which have revolutionized the creation of low-dimensional structures. These structures, encompassing thin films, mesoscopic forms, and nanostructures, hold immense significance for Condensed Matter Physics, particularly in opto- and micro-electronics. Their uniqueness stems from the epitaxial growth of semiconductors, facilitated by cutting-edge crystal growth methods.

Sérgio Magalhães’s fascination with enhancing the attributes of these materials led to delve into the realm of Nuclear Sciences. Here, Sérgio Magalhães discovered the pivotal role of controlled processes in modifying materials, particularly through ex-situ incorporation of ion species. This method allows for precise manipulation of dopant concentrations, depth-profiling, and ensuring high purity through mass selection, thereby positioning ion implantation as a key tool for integration into the silicon industry. However, the journey is not without its challenges. On the on hand, the stochastic nature of ion implantation brings forth lattice damage as energetic ions interact and penetrate the semiconductor lattice. While thermal or pressure annealing offers partial relief, the introduction of vacancies and point defects during this process leaves behind residual strain fields that persist beyond annealing. On the other hand, the advanced measurements acquired from X-ray scattering and ion beam techniques demand equally sophisticated computer software tools to simulate their data. In response to this need, the MROX (Multiple Reflection Optimization) package for X-ray diffraction/reflection software has been recently developed. It should be emphasized that program made by Sérgio Magalhães allows to simulate XRD data of advanced semiconductor structure systems (superlattices, nanowires, quantum-dots, thin layers, ion implanted structures) what is impossible in commercial available XRD software. Already, MROX program has been credited in 16 research manuscripts published in reputable international peer-reviewed journals. Driven by the quest to unravel these complexities and enhance material properties, Sérgio Magalhães embarked on a mission to conduct non-destructive structural investigations. Leveraging X-ray and ion beam techniques, Sérgio Magalhães’s goals are to gain deeper insights into the mechanisms of damage accumulation in crystals. The success has been bolstered by over 60 research publications, facilitated by numerous international collaborations, including partnerships with esteemed institutions such as the Institute of Physics at the Polish Academy of Sciences.

SPOTLIGHT TALK – 21/06/2024

The Warsaw Doctoral School in Natural and Biomedical Sciences and
the Institute of Physics PAS cordially invites you to a SPOTLIGHT TALK.

The talk is given by Prof. Dr. Ing. Rachid BENNACER (Labo LMPS / Dpt Enseign./Recherche: Génie Civil & Envir., Paris, France).

When and where?

21st June 2024, 11:00 am
at the IP PAS Leonard Sosnowski Auditorium, duration: 45 min + question time

Abstract

In the first part, the talk will focus on capillary rise mechanisms in heterogeneous porous material with different capillary sizes. Both theoretical and experimental work are performed to investigate the time evolution and the exchange at the interface of different porous media. It contains the homogeneous capillary (without layer exchange), which is presented to distinguish the different characteristic times and the liquid capillary rise regimes. Considering gravity effect, shear stress and inertia, three regimes are distinguished theoretically and experimentally based on these two dimensionless parameters (Bo and Ga). Theoretical analysis and simulation results show the capillary rise in tendency and the appearance of oscillatory phenomenon. The heterogeneous porous media are also investigated. A multilayer domain is adopted to model the multiple distribution in capillary sizes. The interaction between these layers (different equivalent capillary sizes) demonstrate how the cooperation appears in nature so as to fit with the optimal situation of fast filling the porous media or the equivalent in drying. Experimental results on both homogeneous and heterogenous cases have a favorable effect on the imbibition enhancement.  In the second part, the talk will complete with the local and global evaporation in such complex porous media.

This event is supported by the Polish National Agency for Academic Exchange, grant no.  BPI/STE/2021/1/00034/U/00001.

About the speaker

Prof. Dr. Ing. Rachid BENNACER: is an Engineer in Mechanical field (1989), and he got his PhD thesis at Pierre et Marie Curie University (Paris 6) in 1993. He worked as lecturer in the University Paris XI (1993/94), became an associate professor at Cergy Pontoise University in 1994 and full Professor in 2008. He moved as senior Professor to the prestigious school Ecole Normale Superieure (Paris-Saclay) since 2010. He becomes in 2017 an Exceptional National Class Professor. He is also adjunced professor at Tianjin Uni. Of comm. (China) and UMB Univ. He assumed several responsibilities, director of the LEEVAM research team (2003-2007), Licence degrees & Aggregation title (2008-2011), Master research degree (2011 2013), Transfer and Environmental Research Unit (CNRS LMT-Lab) (since July 2012), dean of Civil/Environmental department (Oct. 2012/Sep. 2016) and 2019/2023 Coordinate International Affairs Related to Ph.D Univ. Paris-Saclay; President of ENS Paris-Saclay Special Executive committee and vice Dean of the ISI Graduate school. His present research activity is within the LMPS laboratory. His Research field covers wide spectrum and several domains. It covers the building material for energy applications or on durability aspect, renewable and energy system. The expertise covers the direct numerical simulation including CFD coupling on multi-scales. The previous approach is consolidated by analytical or reduction approach in order to identify the instabilities and global behavior bifurcation and similarity controlling parameters in multiphysics situations. He published around 10 book chapters and more than 300 referenced international journals (Rank A).

Summer School on Organic Synthesis under Non-classical Conditions

Mamy przyjemność zaprosić Państwa na konferencję pod tytułem “Summer School on Organic Synthesis under Non-classical Conditions”, która odbędzie się w dniach 2-6 września 2024 roku, w Instytucie Chemii Organicznej PAN.

Będziemy gościć czołowych naukowców z całej Europy, którzy podzielą się najnowszymi osiągnięciami w dziedzinie syntezy organicznej prowadzonej w niestandardowych warunkach.

Tematyka Szkoły Letniej skupi się na trzech kluczowych obszarach syntezy organicznej:

  • Fotochemia
  • Elektrochemia
  • Mechanochemia

Studenci ze Szkoły Doktorskiej Warsaw4PhD są zwolnieni z opłaty konferencyjnej.

Do zobaczenia wkrótce!

The STER Summer School in Redox Processes

Five days of science 10-14 June 2024

The STER workshop runs over five days, with each day dedicated to a specific topic. The school is a workshop aimed at PhD students and young researchers in physical chemistry to familiarise themselves with the latest topics in physical chemistry.

World class lecturers

A tutorial lecture will be given by an internationally renowned speaker followed by lectures by students and local experts.

Register now – limited number of places.

Don’t miss this opportunity to learn from our guests and get feedback on your research. Young researchers can apply for talks or poster presentations.

SPOTLIGHT TALK – 19/06/2024

The Warsaw Doctoral School in Natural and Biomedical Sciences and the Institute of High Pressure Physics PAS cordially invites you to a SPOTLIGHT TALK.

The talk is given by Dr. Cecilia Mortalo (Consiglio Nazionale delle Ricerche – Instituto di Chemica della Materia Condensata e di Technologie per l’Energia (CNR-ICMATE), Corso Stati Uniti 4, 35127 Padova, Italy).

When and where?

19th June 2024 2024, 12:30 pm
at the IHPP PAS New Technologies Building, Al. Prymasa Tysiąclecia 98 Duration: 60 min + more

Abstract

Hydrogen separation and purification technology is a key element in the use of H2 as an energy carrier and in other important technological applications. Dense ceramic materials based on mixed ionic and electronic conductors (MIEC) are currently attracting growing interest for their potential application in H2 separation membranes or in catalytic membrane reactors at T > 600°C. Indeed, these membranes allow a selective non-galvanic separation by incorporating H2 in their crystal structure as charged protonic defects and electrons/holes that are transported to the opposite side of the membrane under an H2 partial pressure gradient, i.e. without any external energy. When used as membrane reactors, they also combine separation and reaction in a single unit, increasing efficiency.

In this context, ceramic-ceramic (cer-cer) composites have gained interest in the last 5 years due to their improved hydrogen permeability compared to single phase materials. Among these, dual-phase membranes based on ceria zirconate perovskites and doped ceria oxides have demonstrated remarkable performance as dense H2-separation membranes, with H2 flux values among the highest reported in the literature for this type of system.

The seminar will provide a comprehensive overview of the use of proton conducting ceramic membranes for hydrogen separation, with particular emphasis on dual-phase ceramic membranes based on BaCe0.65Zr0.20Y0.15O3-δ (BCZ20Y15) perowskite and doped ceria (Ce0.85M0.15O2-δ M = Y or Gd, YDC15 or GDC15) composites. The preparation methods, hydrogen permeability and chemical stability issues are also discussed.

SPOTLIGHT TALK – 13/06/2024

The Warsaw Doctoral School in Natural and Biomedical Sciences and
the Institute of Physics PAS cordially invites you to a SPOTLIGHT TALK.

The talk is given by Dr. Andrés Ayuela (Centro de Física de Materiales CSIC-UPV/EHU, Donostia International Physics Center (DIPC), San Sebastián, Spain)

When and where?

13th June 2024, 10:30 am
at the IF PAN Auditorium, durations: 45 min + question time

Abstract

In this talk I will present a few success case studies where calculations using atomistic techniques, typical of the nanoscale, have been employed to study problems in cementitious materials. I will begin by describing challenges associated with powder cement, the clinker, with compounds such as belite, which are currently a key focus in the design of low CO2 cements. Secondly, I will proceed to describe the compounds that are formed following the hydration of the clinker. These include the C-S-H gel, which constitutes the cement glue that holds the aggregates together, as well as other secondary compounds such as portlandite. Furthermore, I will review the characterisation of the C-S-H gel using NMR techniques and how this technique can be used to define the nanoscale structure of the gel phases. Finally, I will examine the potential role of nanoadditions that could be intentionally incorporated into cement pastes.

Andrés Ayuela got his PhD in physics at University of Valladolid in 1995. He was postdoctoral reasercher at Dresden University in Technology in 1996 – 1997, in 1998 – 2003 he was reasercher at Helsinki University of Technology (including two years Marie Curie fellowship). Since 2003 he works in San Sebastián, holding scientific positions at Donostia International Physics Center and Centro de Física de Materiales CSIC-UPV/EHU.

His research interests focus on the atomistic simulations of structural, optical and magnetic properties of solids and nanostructures, such as graphene and 2D materials, nanotubes, alloys, layered oxides and cements. He published over 120 peer-reviewed papers in such journals like Physical Review Letters, Applied Physics Reviews, Advanced Materials, Nano Letters, Nanoscale, Nanophotonics, 2D Materials, Chemistry of Materials, Cement and Concrete Research, Carbon and Acta Materialia (H-index = 38).

This event is supported by the Polish National Agency for Academic Exchange, grant no. BPI/STE/2021/1/00034/U/00001.

SPOTLIGHT TALK – 06/06/2024

The Warsaw Doctoral School in Natural and Biomedical Sciences and the Center for Theoretical Physics PAS cordially invites you to a SPOTLIGHT TALK.

The talk is given by prof. Adi Nusser (Technion University Haifa, Israel).

When and where?

06th June 2024, 5:00 pm
at the Center for Theoretical Physics PAS, al. Lotników 32/46, Auditorium Duration: 90+ min

Abstract

Galaxies form at the peaks of the dark matter density fields, and as such, their spatial distribution is correlated with the dark matter density field, albeit not in a straightforward relationship. In contrast, by virtue of the equivalence principle, galaxy peculiar motions (deviations from a pure Hubble flow) faithfully trace the dark matter flow across large scales, away from regions affected by stellar and AGN feedback (such as supernova explosions and the ejection of energy via accretion onto galactic supermassive black holes).
The lecture will focus on the challenges in extracting cosmological information on the nature of dark matter, dark energy, and the fundamental theory of gravity from observations of the galaxy distribution and peculiar motions in the late Universe (within a few hundred Megaparsecs from us). It will review a few of the key analysis methods developed over the years and delve into the use of AI/ML, addressing the question of whether this methodology will eventually replace previous tools.

This event is supported by the Polish National Agency for Academic Exchange, grant no. BPI/STE/2021/1/00034/U/00001.

CANCELLED! SPOTLIGHT TALK – 10/06/2024

The Warsaw Doctoral School in Natural and Biomedical Sciences and the Institute of High Pressure Physics PAS cordially invites you to a SPOTLIGHT TALK.

The talk is given by Prof. Horst Hahn (Sustainable Chemical, Biological and Materials Engineering, University of Oklahoma, Norman, OK, United States of America; Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany).

When and where?

Abstract

Advanced materials are typically characterized by complex nano- and microstructures with various phase compositions, grain sizes, chemical inhomogeneity or homogeneity, crystalline and amorphous structures, all leading to metastability. Over the past 30 years, many new materials have been developed making use of these possibilities and leading to many interesting properties. Prominent examples of such materials are metallic glasses, nanocrystalline materials and high entropy materials. In recent years, new ideas and novel synthesis routes have shown the way to advanced materials with yet unknown structures and properties. The talk will present examples of synthesis, characterization and properties of advanced materials with amorphous and crystalline structures: nanoglasses, cluster-assembled amorphous and crystalline materials and high entropy oxides.

SPOTLIGHT TALK – 21/05/2024

The Warsaw Doctoral School in Natural and Biomedical Sciences and the Institute of High Pressure Physics PAS cordially invites you to a SPOTLIGHT TALK.

The talk is given by Dr. Andriy Palasyuk (Critical Materials Institute, Ames Laboratory, USA).

When and where?

21st May 2024, 11:00 am
at the IHPP PAS New Technologies Building, Al. Prymasa Tysiąclecia 98, seminar room, 2nd floor
Duration: 60 min + more

Abstract

A gap in the market exists between super strong neodymium magnets and less sensitive ferrite magnets. This gap means that compromises are made in engineering items like car sensors or wind turbine rotors. The Critical Materials Institute is working on a cerium-based magnet that will hit the sweet spot between powerful rare earth magnets and the much weaker ferrites. The magnet is process effective and less susceptible to supply chain disruptions. Its unique intra-granular coercivity mechanism does not require complicated microstructure developments and opens potential for advanced manufacturing.

SPOTLIGHT TALK – 08/05/2024

The Warsaw Doctoral School in Natural and Biomedical Sciences and the Institute of High Pressure Physics PAS cordially invites you to a SPOTLIGHT TALK.

The talk is given by Prof. Eugen Rabkin (Department of Materials Science and Engineering, Technion – Israel Institute of Technology, 3200003 Haifa, Israel).

When and where?

8th May 2024 2024, 12:30 pm
at the IHPP PAS New Technologies Building, Al. Prymasa Tysiąclecia 98 Duration: 60 min + more

Abstract

We studied the uniaxial compression behavior of micro- and nanoparticles of several elemental metals (Au, Ni, Ag, Mo, Pt) and alloys (Ni-Co, Ni-Fe, Au-Ag, Cu-Au). The particles were obtained by solid state dewetting of thin metal films and bi-layers deposited on sapphire substrates. The high homological temperatures employed in dewetting process ensure the low concentration of dislocations and their sources in the particles. The particles compressed with a flat diamond punch exhibit purely elastic behavior up to very high values of strain approaching 10%, followed by a catastrophic plastic collapse. The uniaxial yield strength of the particles defined as an engineering stress at the point of catastrophic collapse reached the astonishing values of 34, 41 and 46 GPa for the smallest faceted particles of Ni, disordered Cu3Au, and Mo, respectively. The atomistic molecular dynamic simulations of the particle compression demonstrated that the catastrophic plastic yielding of the particles is associated with the multiple nucleation of dislocations at the facet corners or inside the particles. The latter, homogeneous nucleation mode resulted in higher particle strength. The size effect in compression was observed both in the experiments and in atomistic simulations, with smaller particles exhibiting higher compressive strength. We discussed the stronger size effect observed in the experiment (as compared with simulations) in terms of the effect of residual defects trapped in the particles. Finally, we produced Au-Ag core-shell nanoparticles by coating the single crystalline Ag nanoparticles with a polycrystalline Au shell. The core-shell nanoparticles exhibited much lower strength than their single crystalline pure Ag counterparts. We related this decrease in strength with the active role of grain- and interphase boundaries in the polycrystalline Au shell in decreasing the energy barrier for dislocations nucleation.