Wave Function Engineering on Superconducting Substrates: Chiral Yu-Shiba-Rusinov Molecules.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Mechanics

Background:

• Magnetic adatoms on superconductors form Yu-Shiba-Rusinov (YSR) states.
• YSR states are crucial for developing topological superconductivity.
• Engineering complex wave function symmetries is an active research area.

Purpose of the Study:

• To demonstrate that YSR states can be used to engineer intricate wave function symmetries.
• To investigate the hybridization of YSR states in engineered adatom structures.
• To explore the potential of superconductor substrates in breaking symmetries for novel quantum states.

Main Methods:

• Assembling iron (Fe) adatom structures on the quasi-two-dimensional superconductor 2H-NbSe2.
• Utilizing scanning tunneling microscopy (STM) to observe and characterize YSR states.
• Analyzing the spatial extent and hybridization of YSR wave functions.

Main Results:

• YSR wave functions exhibit large spatial extent, enabling hybridization even at significant adatom distances.
• The 2H-NbSe2 substrate was used to break structural symmetries, leading to novel hybridized YSR states.
• Engineered chiral YSR wave functions were successfully created using triangular adatom arrangements.

Conclusions:

• YSR states provide an ideal platform for engineering complex wave function symmetries.
• The substrate's symmetry-breaking potential allows for the creation of quantum states not found in isolated molecules.
• This work expands the possibilities for designing novel quantum states using magnetic adatoms on superconductors.