NCN Sonata-bis 7 ST Project
In February 2018, the National Science Centre granted me 1.4 million PLN to carry out a 5-year research project titled "The role of resonance states, spin-orbit coupling, and disorder in the superconductivity of selected materials" (no. 2017/26/E/ST3/00119). The project was completed in April 2024.
In the project, we undertook theoretical studies of superconductivity in three areas: (1) electron-phonon properties and the mechanism of superconductivity in doped semiconductors where a so-called resonance state forms on the impurity atom; (2) superconductivity in systems containing heavy elements and non-centrosymmetric ones, where relativistic spin-orbit coupling plays an important role; (3) superconductivity and the impact of disorder on the properties of a new class of materials, so-called high-entropy alloys. The fourth research area was the development of numerical tools for studying superconductivity.
Our research was based on first-principles calculations of the properties of real compounds with a given crystal structure and composition. Using both existing and newly created computational tools for the project, we determined the fundamental electronic, phononic, and superconducting properties of many materials.
The project team: Bartlomiej Wiendlocha, Sylwia Gutowska, Gabriel
Kuderowicz, Paweł Wójcik, Kacper Pryga, Kinga Jasiewicz, Kamil
Kutorasiński.
Figure: The anisotropis structure of the 2 superconducting gaps in ScAu2Al.
Figure: Formation of the strongly-coupled anisotropic superconductivity in
the Pb-Bi alloy..
The most significant achievements of the project include:
- Demonstrating that the resonance state boosts the electron-phonon coupling strength in PbTe:Tl and SnTe:In.
- Quantitatively describing the resonance scattering mechanism, showing that the resonance state in PbTe:Tl and SnTe:In determines both the low-temperature transport properties (carrier mobility, residual resistivity) and the high-temperature thermoelectric properties (thermopower) of these materials.
- Proposing a new method for detecting the resonance state through the analysis of residual resistivity.
- Demonstrating the qualitatively different impact of spin-orbit interaction on the superconductivity of materials, depending on the type of dominant orbitals at the Fermi level (contraction/expansion of p/d orbitals).
- Demonstrating that the electron-phonon interaction in non-centrosymmetric ThCoC2 is strong enough to induce phonon-mediated superconductivity with the observed critical temperature Tc (spin fluctuations were postulated before). Proposing methods to verify this hypothesis (simulation of pressure effects on Tc and the isotope effect). Demonstrating that the phonon mechanism qualitatively explains the observed strong increase in Tc when ThCoC2 is doped with nickel.
- Demonstrating that the superconductivity of ThCoC2 exhibits unconventional properties that cannot be described by isotropic formalism.
- Indicating the anisotropic and strongly coupled nature of superconductivity in ScAu2Al and Pb0.64Bi0.36.
- Identifying the "phonon engineering" mechanism in Laves phases SrIr2/SrRh2, where the "relaxation" of the Ir/Rh atom tetrahedral network lowers the frequency of phonon branches key to superconductivity while maintaining a strong electronic contribution to the coupling constant λ. This explains the strongly coupled superconductivity in Laves phases compared to Ir/Rh metal and appears to be a more general mechanism present in other Laves phases.
- Theoretically discovering superconductivity in LiPd2Si, later confirmed experimentally.
- Demonstrating the existence of dynamic instability in LiPd2Ge and its correlation with superconductivity.
- Explaining the mechanism of Tc enhancement by pressure in the high-entropy alloy TaNbHfZrTi.
- Investigating the role of disorder in the superconductivity of TaNbHfZrTi: demonstrating the weak impact of chemical disorder and the strong impact of structural disorder (lattice distortions) on the electronic structure and electron-phonon coupling.
- Indicating a strong disorder-induced scattering effect, competing with superconductivity, in the high-entropy alloy (ScZrNb)1-x(RhPd)x.
- Developing tools for numerical studies of the thermodynamics of the superconducting state within the Eliashberg formalism.
- Applying the anisotropic density functional theory for superconductors to study the superconducting gap and Tc without free parameters.
The funds allocated for the project were used, among other things, to purchase a multi-processor computing cluster, software, scholarships for PhD and master's students, conference trips, materials, and computer equipment.
Publications Resulting from the Project
Several works are in preparation. Published works:
- Sylwia Gutowska, Karolina Górnicka, Paweł Wójcik, Tomasz Klimczuk,
Bartlomiej Wiendlocha,
"Anisotropic, multiband, and strong-coupling
superconductivity of the Pb0.64Bi0.36 alloy", Phys. Rev. B 110,
214510
(2024) (Highlighted as Editors' Suggestion). Preprint:
https://arxiv.org/abs/2411.18315
- Hanna Świątek, Sylwia Gutowska, Michał J. Winiarski, Bartlomiej Wiendlocha, Tomasz Klimczuk,
"Superconductivity in Ternary Mg4Pd7As6", Advanced Electronic Materials 2024
- Kinga Jasiewicz, Sylwia Gutowska, Janusz Tobola, Bartlomiej
Wiendlocha, "Electronic Structure and Electron-Phonon Coupling
Calculations
for bcc HEA Superconductors Ta-Nb-Hf-Zr-Ti", w "High-Entropy
Alloy
Superconductors. Exotic Properties, Applications and Materials
Design" ed.
Jiro Kitagawa, Yoshikazu Mizuguchi, Springer 2024.
- Shantanu Misra, Bartlomiej Wiendlocha, Soufiane El Oualid, Anne Dauscher, Bertrand Lenoir, Christophe Candolfi, "Unravelling the need for balancing band convergence and resonant level in Sn1−x−yInxMnyTe for high thermoelectric performance", Journal of Materials Chemistry A 2024, DOI: 10.1039/D3TA05468C
- Kinga Jasiewicz, Janusz Tobola, Bartlomiej Wiendlocha, "Local
distortions of the crystal structure and their influence on the electronic
structure and superconductivity of the high-entropy
alloy (TaNb)0.67(HfZrTi)0.33",
Physical Review B 108, 224505
(2023).
Prepront: https://arxiv.org/abs/2311.16767.
- Gabriel Kuderowicz, Bartlomiej Wiendlocha, "Strong-coupling
superconductivity of the Heusler-type compound ScAu2Al: Ab-initio studies",
Physical
Review B 108, 224501 (2023).
Preprint: https://arxiv.org/abs/2311.06075.
- Sylwia Gutowska, Alicja Kawala, Bartlomiej Wiendlocha,
"Superconductivity near the Mott-Ioffe-Regel limit in the high-entropy alloy
superconductor (ScZrNb)1-x(RhPd)x with a CsCl-type lattice", Physical Review B
108, 064507 (2023). Preprint: https://arxiv.org/abs/2308.03153.
- Sylwia Gutowska, Bartlomiej Wiendlocha, Tomasz Klimczuk, Michał J.
Winiarski, "Superconductivity in Bismuth Pyrochlore Lattice Compounds RbBi2
and CsBi2: The Role of Relativistic Effects", Journal of Physical
Chemistry C 127, 14402 (2023).
- Shantanu Misra, Bartlomiej Wiendlocha, Janusz Tobola, Petr Levinský,
Jiří Hejtmánek, Sylvie Migot, Jaafar Ghanbaja, Anne Dauscher, Bertrand
Lenoir, and Christophe Candolfi, Influence of In-induced resonant level on
the normal-state and superconducting properties of Sn1.03Te,
Physical Review B
106, 075205
(2022).
- Gabriel Kuderowicz, Paweł Wójcik, and Bartlomiej Wiendlocha, "Pressure
effects on the electronic structure, phonons, and superconductivity of
noncentrosymmetric ThCoC2", Physical Review B
105, 214528 (2022). Preprint: https://arxiv.org/abs/2206.09598
- Sylwia Gutowska and Bartlomiej Wiendlocha, "Electronic structure of CeIr3
superconductor: DMFT studies", Journal of Magnetism and Magnetic Materials,
547, 168917 (2022).
Preprint: https://arxiv.org/abs/2201.01206.
- Gabriel Kuderowicz and Bartlomiej Wiendlocha, "The effect of Ni doping
on the electronic structure and superconductivity in the noncentrosymmetric
ThCoC2",
Journal of Magnetism and Magnetic Materials 546, 168688 (2022). (open access).
- Taras Parashchuk, Bartlomiej Wiendlocha, Oleksandr Cherniushok, Rafal Knura, and Krzysztof T.
Wojciechowski, High Thermoelectric Performance of p-Type PbTe Enabled by the
Synergy of Resonance Scattering and Lattice Softening,
ACS Applied Materials & Interfaces
13, 49027 (2021)
- Gabriel Kuderowicz, Paweł Wójcik, and Bartlomiej Wiendlocha,
Electronic structure, electron-phonon coupling, and superconductivity in
noncentrosymmetric ThCoC2 from ab initio calculations", Physical Review B
104,
094502 (2021). preprint: https://arxiv.org/abs/2105.03472
- Karolina Górnicka, Gabriel Kuderowicz, Michał J. Winiarski, Bartłomiej
Wiendlocha, Tomasz Klimczuk, "Superconductivity in LiGa2Ir Heusler type compound with
VEC = 16", Scientific
Reports 11, 16517 (2021) (open access)
- Sylwia Gutowska, Karolina Górnicka, Paweł Wójcik, Tomasz Klimczuk, and
Bartlomiej Wiendlocha, "Strong-coupling superconductivity of
SrIr2 and SrRh2: Phonon engineering of metallic Ir and Rh"
Physical Review B
104, 054505
(2021).preprint: https://arxiv.org/abs/2108.03692
- M. J. Winiarski, G. Kuderowicz, K. Górnicka, L. S. Litzbarski, K.
Stolecka, B. Wiendlocha, R. J. Cava, and T. Klimczuk,
"MgPd2Sb: A Mg-based Heusler-type
superconductor", Physical Review B
103, 214501 (2021).
- Bartlomiej Wiendlocha, Shantanu Misra, Anne Dauscher, Bertrand Lenoir and Christophe
Candolfi, "Residual resistivity as an independent indicator of resonant
levels in semiconductors", Materials Horizons 8, 1735 (2021)
- Karolina Górnicka, Xin Gui, Bartlomiej Wiendlocha, Loi T. Nguyen, Weiwei
Xie, Robert J. Cava, Tomasz Klimczuk, "NbIr2B2 and TaIr2B2 - New Low
Symmetry Noncentrosymmetric Superconductors with Strong Spin-Orbit Coupling"
Advanced Functional Materials
31, 2007960 (2021)
- Karolina Górnicka, Gabriel Kuderowicz, Elizabeth M. Carnicom, Kamil
Kutorasiński, Bartlomiej Wiendlocha, Robert J. Cava, and Tomasz Klimczuk,
"Soft-mode enhanced type-I superconductivity in LiPd2Ge", Physical Review B
102, 024507, 2020 (highlighted as Editors' suggestion).
- Karolina Górnicka, Sylwia Gutowska, Michał J. Winiarski, Bartlomiej
Wiendlocha, Weiwei Xie, R. J. Cava, Tomasz Klimczuk, "Superconductivity on a
Bi Square Net in
LiBi",
Chemistry of
Materials 32, 3150 (2020)
- Shantanu Misra, Bartlomiej Wiendlocha, Janusz Tobola, Florian Fesquet, Anne Dauscher,
Bertrand Lenoir and Christophe Candolfi, "Band structure engineering in
Sn1.03Te through an In-induced resonant level"
Journal of Materials Chemistry C 8, 977 (2020).
- Karolina Górnicka, Debarchan Das, Sylwia Gutowska, Bartłomiej
Wiendlocha, Michał J. Winiarski, Tomasz Klimczuk, and Dariusz Kaczorowski,
"Iridium 5d-electron driven superconductivity in ThIr3",
Phys. Rev. B
100, 214514 (2019). preprint: https://arxiv.org/abs/1912.12882
- K. Jasiewicz, B. Wiendlocha, K. Górnicka, K. Gofryk, M. Gazda, T.
Klimczuk, and J. Tobola, "Pressure effects on the electronic structure and superconductivity of (TaNb)0.67(HfZrTi)0.33 high entropy
alloy",
Phys.
Rev. B 100, 184503 (2019)preprint: https://arxiv.org/abs/1910.08312
- Sylwia Gołąb and Bartłomiej Wiendlocha, "Electron-phonon
superconductivity in CaBi2 and the role of spin-orbit interaction",
Phys. Rev. B 99, 104520 (2019)
preprint: https://arxiv.org/abs/1904.00650
- Karolina Górnicka, Elizabeth M Carnicom, Sylwia Gołąb, Marcin Łapiński,
Bartłomiej Wiendlocha, Weiwei Xie, Dariusz Kaczorowski, Robert J Cava and Tomasz
Klimczuk, "CeIr3: superconductivity in a phase based on tetragonally close
packed clusters", Superconductor
Science and Technology 32,025008 (2019).
- Tai Kong, Karolina Górnicka, Sylwia Gołąb, Bartlomiej Wiendlocha,
Tomasz Klimczuk, and Robert J. Cava, "A Family of Pb-based Superconductors
with Variable Cubic to Hexagonal Packing", Journal of the Physical Society
of Japan 87, 074711 (2018) preprint: https://arxiv.org/abs/1805.09835
- Bartlomiej Wiendlocha, "Thermopower of thermoelectric materials with
resonant levels: PbTe:Tl versus PbTe:Na and Cu1-xNix",
Physical Review B 97, 205203 (2018).