Shadow on the wall cast by an Abrikosov vortex

Area of Science:

• Condensed Matter Physics
• Superconductivity
• Surface Science

Background:

• D-wave superconductors exhibit a zero-energy peak in their quasiparticle spectrum due to Andreev bound states.
• This peak is maximal when the nodal direction of the d-wave pairing potential is perpendicular to the surface boundary.

Purpose of the Study:

• To investigate the influence of a single Abrikosov vortex positioned near a reflecting boundary on the zero-energy density of states in a d-wave superconductor.
• To analyze the stability and characteristics of the observed spectral changes across different theoretical models and physical parameters.

Main Methods:

• Theoretical examination of the quasiparticle spectrum in the presence of a single Abrikosov vortex and a boundary.
• Analysis of the zero-energy density of states and its spatial distribution.
• Simulation across various models for the Abrikosov vortex, mean free paths, and vortex-boundary distances.

Main Results:

• A clear splitting of the low-energy peak in the quasiparticle spectrum was observed.
• A suppression of the zero-energy density of states was found in a shadow-like region extending from the vortex to the boundary.
• This suppression effect demonstrated stability across different vortex models, mean free paths, and distances.

Conclusions:

• The presence of a single Abrikosov vortex near a boundary significantly modifies the zero-energy density of states in d-wave superconductors.
• The observed spectral splitting and suppression are robust phenomena with potential implications for understanding surface states and vortex physics.
• These findings are expected to influence differential conductance and tunneling spectroscopy measurements at low energies.