General information about the project

Nearly half a century has passed since P. W. Anderson published in Science his seminal paper More is Different. In this paper Anderson discusses the hierarchical structure of science and puts forward the conjecture that the knowledge of behavior of a few particles cannot be extrapolated to predict the behavior of more complex systems. This straightforwardly leads to the conclusion that with increasing the system’s complexity, some completely new properties may emerge. In fact, over recent decades we have witnessed several astonishing discoveries, with topologically protected states of matter (Nobel awarded to Thouless, Haldane and Kosterlitz in 2016) being a very important example. Such states are very robust against local perturbations, since they are protected by symmetry, and can extend over entire sample. This makes them very promising for quantum spintronics and quantum computation and, in fact, puts their investigations in the forefront of nowadays physics. Besides, topological materials also constitute an excellent playground for more fundamental research. In particular, it turns out that the long-searched Majorana fermions, i.e. particles that are their own antiparticles, predicted by Ettore Majorana already in 1937, can emerge at the ends of topological superconducting wires as zero-energy quasiparticles.

The Majorana quasiparticles and their interactions with strongly correlated low-dimensional systems are the central object of interest of this research project.

The emergence of Majorana quasiparticles at the ends of topological superconducting nanowires can be confirmed by performing transport spectroscopy experiments, where their presence gives rise to a zero-bias peak in the differential conductance of the device. Moreover, Majorana quasiparticles can also affect the transport behavior of side-attached zero-dimensional systems, such as quantum dots, where the leakage of Majorana modes results in fractional value of the conductance. In fact, such hybrid, coupled zero and one-dimensional systems provide an exceptional opportunity to test fundamental interactions between topologically-protected states of matter and various electronic correlations, such as the ones leading to the Kondo effect. The Kondo effect emerges when a magnetic impurity interacts with continuum of states and its signature is an additional resonance in the local density of states of the impurity. The studies of the interplay between the Kondo and Majorana physics have been so far mainly restricted to relatively simple models. Nevertheless, since to understand the behavior of real systems minimal descriptions are not necessarily sufficient, it is important to address the question of what are the transport properties of considered hybrid systems, where more exotic Kondo phenomena can emerge. The investigations will be performed by using the state-of-the-art numerical and analytical methods, which will be appropriately adapted to determine the transport behavior of considered hybrid systems. These methods include, among others, the density-matrix numerical renormalization group method – the approach known for its accuracy in determining the transport properties of nanostructures, or the Keldysh nonequilibrium Green’s function formalism.

Realization period: 21.01.2019 - 20.09.2023

Research team:

Prof. Ireneusz Weymann (PI, Leader of the UAM node)

Prof. Tadeusz Domański (Leader of the UMCS node)

Dr. Krzysztof Wójcik

Dr. Sakineh Vosoughi-nia

Dr. Grzegorz Górski

MSc. Piotr Majek

List of publications

PUBLICATIONS:

  1. R. Taranko, K. Wrześniewski, I. Weymann, T. Domański
    Transient effects in quantum dots contacted via topological superconductor
    Phys. Rev. B 110, 035413 (2024)
  2. K. Wrześniewski, I. Weymann
    Cross-correlations between currents and tunnel magnetoresistance in interacting double quantum dot-Majorana wire system
    Sci. Rep. 14, 7815 (2024)
  3. K. P. Wójcik, T. Domański, I. Weymann
    Signatures of Kondo-Majorana interplay in ac response
    Phys. Rev. B 109, 075432 (2024)
  4. A. Huguet, K. Wrześniewski, I. Weymann
    Spin effects on transport and zero-bias anomaly in a hybrid Majorana wire-quantum dot system
    Sci. Rep. 13, 17279 (2023)
  5. K. P. Wójcik, J. Kroha
    Quantum spin liquid in an RKKY-coupled two-impurity Kondo system
    Phys. Rev. B 107, L121111 (2023)
  6. K. P. Wójcik, J. Kroha
    Asymmetry effects on the phases of RKKY-coupled two-impurity Kondo systems
    Phys. Rev. B 107, 125146 (2023)
  7. K. P. Wójcik, P. Majek
    Majorana Coupling and Kondo Screening of Localized Spins
    Acta Phys. Pol. A 143, 207 (2023)
  8. T. Domański, S. Vosoughi-Nia, A. Kobiałka
    Synergy of Semiconductor Physics and Electron Pairing: Route Towards Novel Topological Materials
    Acta Phys. Pol. A 142, 679 (2022)
  9. P. Majek, G. Górski, T. Domański, I. Weymann
    Hallmarks of Majorana mode leaking into a hybrid double quantum dot
    Phys. Rev. B 106, 155123 (2022)
  10. P. Majek, I. Weymann
    Majorana-Kondo competition in a cross-shaped double quantum dot-topological superconductor system
    J. Magn. Magn. Mater. 549, 168935 (2022)
  11. P. Majek, K. P. Wójcik, I. Weymann
    Spin-resolved thermal signatures of Majorana-Kondo interplay in double quantum dots
    Phys. Rev. B 105, 075418 (2022)
  12. P. Majek, I. Weymann
    Majorana mode leaking into a spin-charge entangled double quantum dot
    Phys. Rev. B 104, 085416 (2021)
  13. J. Barański, M. Barańska, T. Zienkiewicz, R. Taranko, T. Domański
    Dynamical leakage of Majorana mode into side-attached quantum dot
    Phys. Rev. B 103, 235416 (2021)
  14. B. Baran, R. Taranko, T. Domański
    Subgap dynamics of double quantum dot coupled between superconducting and normal leads
    Sci. Rep. 11, 1-15 (2021)
  15. R. Taranko, K. Wrześniewski, B. Baran, I. Weymann, T. Domański
    Transient effects in a double quantum dot sandwiched laterally between superconducting and metallic leads
    Phys. Rev. B 103, 165430 (2021)
  16. K. Wrześniewski, B. Baran, R. Taranko, T. Domański, I. Weymann
    Quench dynamics of a correlated quantum dot sandwiched between normal-metal and superconducting leads
    Phys. Rev. B 103, 155420 (2021)
  17. K. Wrześniewski, I. Weymann
    Magnetization dynamics in a Majorana-wire-quantum-dot setup
    Phys. Rev. B 103, 125413 (2021)
  18. G. Górski, K. Kucab, T. Domański
    Magnetic field effect on trivial and topological bound states of superconducting quantum dot
    J. Phys.: Cond. Matter 32, 445803 (2020)
  19. I. Weymann, K. P. Wójcik, P. Majek
    Majorana-Kondo interplay in T-shaped double quantum dots
    Phys. Rev. B 101, 235404 (2020)
  20. T. Zienkiewicz, J. Barański, G. Górski, T. Domański
    Leakage of Majorana mode into correlated quantum dot nearby its singlet-doublet crossover
    J. Phys.: Cond. Matter 32, 025302 (2019)
  21. A. Kobiałka, T. Domański, A. Ptok
    Delocalisation of Majorana quasiparticles in plaquette-nanowire hybrid system
    Sci. Rep. 9, 12933 (2019)
  22. B. Baran, T. Domański
    Quasiparticles of a periodically driven quantum dot coupled between superconducting and normal leads
    Phys. Rev. B 100, 085414 (2019)