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Updated: Jun 8, 2025
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Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
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Interplay of correlations and Majorana mode from local solution perspective.
Jan Barański1, Magdalena Barańska1, Tomasz Zienkiewicz1
1Department of General Education, Polish Air Force University, ul. Dywizjonu 303 nr 35, 08521 Deblin, Poland.
Summary
We explored a hybrid system of a quantum dot and a topological superconducting nanowire with Majorana modes. Coulomb repulsion and Majorana modes interact, affecting the Majorana mode
Area of Science:
- Condensed Matter Physics
- Quantum Information Science
- Nanotechnology
Background:
- Topological superconducting nanowires host Majorana boundary modes, crucial for topological quantum computing.
- Correlated quantum dots exhibit complex electronic behavior due to Coulomb repulsion.
Purpose of the Study:
- Investigate the quasiparticle spectrum of a hybrid system coupling a quantum dot to a topological superconducting nanowire.
- Uncover the interplay between Coulomb repulsion in the quantum dot and Majorana modes.
Main Methods:
- Exact solution of the low-energy effective Hamiltonian.
- Analytical derivation of spectral weight expressions.
- Comparison with existing theoretical estimations (Ricco et al., 2019).
Main Results:
- Identified a subtle interplay between Coulomb repulsion and Majorana modes.
- Developed analytical expressions showing spectral weight sensitivity to quantum dot energy level and repulsive potential.
- Quantified the spectral weight of the zero-energy Majorana mode coexisting with trivial quantum dot states.
Conclusions:
- The spectral weight of the leaking Majorana mode is tunable via quantum dot parameters.
- Empirical verification of spectral weights is feasible using spin-polarized Andreev spectroscopy.
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