• JRG

    JRG - Junior Research Groups

    Group (Research interest) Electronic Structure and Magnetism
    Leader Igor Di Marco
    Introduction The Junior Research Group "Electronic structure and magnetism" was established in December 2017 to investigate the electronic and magnetic properties of materials. The core of our activity is the development of computational methods for solid-state and many-body physics. Our tools of choice include density-functional theory (DFT), dynamical mean-field theory (DMFT) and their combination (DFT+DMFT). These techniques are then used to model various types of spectroscopies, as e.g. angular- and spin-resolved photoemission spectroscopy (PES), X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD). We use our own tools, as well as others, to study a number of materials, generally involving magnetism and/or strong electronic correlations. Systems attracting our interest include itinerant ferromagnets, transition metal oxides, rare-earth compounds and novel 2-dimensional materials. Understanding these systems is a crucial part of our future technological development, and we believe that first-principles modeling can provide an indispensable help to address this challenge. If you have questions or are interested in a research project in our group, send an email to the JRG leader, using the contact information accessible via the Menu on the left.

    Additional information on the JRG leader is accessible via the following links: Google Scholar , ORCID or Publons.
    Contact & Members
    Name Position Period Email Office Tel Remarks
    Igor Di Marco Leader 2017-12-04
    ~ 2020-12-03
    igor.dimarco(at) 543 1360
    Sagar Sarkar Postdoc
    ~ 2020-12-03
    sagar.sarkar(at) 533 3642
    Dhani Nafday Postdoc
    ~ 2020-09-30
    dhani.nafday(at) 540 1352
    Priyanka Aggarwal Postdoc
    ~ 2019-12-03
    priyanka.aggarwal(at) 516 1285
    Former Members
    Name Position Period Email Office Tel Remarks
    Fabrizio Cossu Postdoc 2019-12-01
    ~ 2020-06-30
    Weiwei Sun Visiting 2019-11-11
    ~ 2020-02-07
    Akshay Gurumoorthi Postdoc 2019-06-24
    ~ 2019-12-31
    Arya Subramonian Postdoc 2018-04-01
    ~ 2019-07-31
    Current Opportunities We welcome Bachelor and Master students to join us for small research projects or summer internships. We have several opportunities in software development for many-body physics, based on python, fortran, C or other programming languages. For Master students who have some basic knowledge in solid state physics or atomic physics, also small computational projects are available, on various arguments. A small compensation is also provided, for logistic support and basic expenses. Postdoctoral scholars with a potential interest in joining our group are invited to send their CV and a motivation/presentation letter, including the contact information of 3 references, to the JRG leader directly.
    Research Focus Our research is focused on computational methods to describe the electronic structure of solids. The JRG leader is one of the main developers of the all-electron density-functional theory code RSPt. RSPt, whose acronym stays for Relativistic Spin-Polarized toolkit, is a joint project across Sweden, USA, France and now Korea. RSPt is based on the full-potential linearized muffin-tin orbital (FP-LMTO) method and has proven to be among the most accurate codes to tackle the Kohn-Sham problem in solids [1]. The main research interest of the JRG leader concerns the combination of density-functional theory (DFT) and dynamical mean-field theory (DMFT). An overview of the research projects that were conducted during his past appointments can be found here. In the present JRG, we focus on methodological developments and investigations of strongly correlated materials, and in particular on the mapping between DFT and Hubbard-like problems. Currently, we are working on the following methodological projects:

    1. the development of a method to extract the Coulomb interaction parameters for 4f electrons in rare-earth based compounds and low-dimensional systems;
    2. the development of a method to extract inter-shell couplings without ad-hoc assumptions, to be applied in nanomagnetism;
    3. the development of our own machinery for X-ray absorption spectroscopy, in analogy to our previous study on transition metal monoxides [2];
    4. the development of a proper formalism for spin- and angle-resolved photoemission spectroscopy, possibly including beyond dipole contributions [3];
    5. the treatment of disorder in electronic structure theory, FP-LMTO in general and RSPt in particular.

    Applications of our techniques are mainly directed towards strongly correlated (magnetic) materials, and are often connected to collaborations with important experimental groups. Some non-methodological topics we have been recently investigating include:

    1. the electronic and magnetic properties of interfaces of Heusler compounds [4] and the formation of a 2-dimensional electron liquid at their surfaces [5];
    2. the electronic and magnetic properties of the prototypical dilute magnetic semiconductor Mn-doped GaAs [6];
    3. the formation and stability of charge-density waves in 2-dimensional materials [7];
    4. the physics of isolated rare-earth adatoms, as a laboratory for single-objects nanomagnets;
    5. valence and core spectroscopy of transition metal oxides [8, 9].

    This list of projects does not want to be exhaustive, but simply provide an overview of our major lines of research. If you are interested in knowing more about our research, please contact the JRG leader or the most senior group members. We will be happy to discuss what we are doing and what impact this may have for physics and society.
    Title Measuring the Intra-Atomic Exchange Energy in Rare-Earth Adatoms
    Journal Title
    All Authors M. Pivetta, F. Patthey, I. Di Marco, A. Subramonian, O. Eriksson, S. Rusponi, and H. Brune
    DOI/Arxiv No. 10.1103/PhysRevX.10.031054
    Title A combined machine learning and density functional theory study of binary Ti-Nb and Ti-Zr alloys: Stability and Young\'s modulus
    Journal Title
    All Authors S. Xiong, X. Li, X. Wu, J. Yu, O. I. Gorbatov, I. Di Marco, P. Kent, W. Sun
    DOI/Arxiv No. 10.1016/j.commatsci.2020.109830
    Title Full-scale analytical perturbation calculation of He-isoelectronic series with Hydrogenic bound states via Greens function expansion (monopole) of Coulomb interactions
    Journal Title
    All Authors S. Sharma, P. Aggarwal, and R. K. Hazra
    DOI/Arxiv No. 10.1080/00268976.2020.1770881
    Title Multi-electron anisotropic quantum dots/TMDCs/CNT families under magnetic field: analytical treatment to first Brillouin zone by Fermi liquid model
    Journal Title
    All Authors P. Aggarwal, S. Sharma, and R. K. Hazra
    DOI/Arxiv No. 10.1080/00268976.2020.1761472
    Title Lattice dynamics of palladium in the presence of electronic correlations
    Journal Title
    All Authors W. H. Appelt, A. �stlin, I. Di Marco, I. Leonov, M. Sekania, D. Vollhardt, and L. Chioncel
    DOI/Arxiv No. 10.1103/PhysRevB.101.075120
    Title Localized versus itinerant character of 4f-states in cerium oxides
    Journal Title
    All Authors H. C. Herper, O. Y. Vekilova, S. I. Simak, I. Di Marco, and O. Eriksson
    DOI/Arxiv No. 10.1088/1361-648X/ab6e92
    Title Analysis of the linear relationship between asymmetry and magnetic moment at the M-edge of 3d transition metals
    Journal Title
    All Authors S. Jana, R. S. Malik, Y. O. Kvashnin, ..., I. Di Marco, ..., and O. Karis
    DOI/Arxiv No. 10.1103/PhysRevResearch.2.013180
    Title Strain-induced stripe phase in charge ordered single layer NbSe2
    Journal Title
    All Authors F. Cossu, K. Palotas, S. Sarkar, I. Di Marco, and A. Akbari
    DOI/Arxiv No. 10.1038/s41427-020-0207-x
    Title Magnetic two-dimensional electron liquid at the surface of Heusler semiconductors
    Journal Title
    All Authors S. Keshavarz, I. Di Marco, D. Thonig, L. Chioncel, O. Eriksson, and Y.O. Kvashnin
    DOI/Arxiv No. 10.1103/PhysRevMaterials.4.021401
    Title Unveiling hidden charge density waves in single-layer NbSe2 by impurities
    Journal Title
    All Authors F. Cossu, A.G. Moghaddam, K. Kim, H. A. Tahini, I. Di Marco, H.-W. Yeom, and A. Akbari
    DOI/Arxiv No. 10.1103/PhysRevB.98.195419
    Title Element- and momentum-resolved electronic structure of the dilute magnetic semiconductor manganese doped gallium arsenide
    Journal Title
    All Authors S. Nem��k, M. Gehlmann, ..., I. Di Marco, ..., and C.S. Fadley
    DOI/Arxiv No. 10.1038/s41467-018-05823-z
    Title Half-metallicity and magnetism in the Co2MnAl/CoMnVAl heterostructur
    Journal Title
    All Authors I. Di Marco, A. Held, S. Keshavarz, Y.O. Kvashnin, and L. Chioncel
    DOI/Arxiv No. 10.1103/PhysRevB.97.035105