Doping-Induced Quantum Spin Hall Insulator to Superconductor Transition

Area of Science:

• Condensed Matter Physics
• Quantum Materials
• Superconductivity

Background:

• A quantum spin Hall insulating state exhibits unique properties, including charge 2e skyrmion textures.
• Spontaneous symmetry breaking drives this insulating state.
• Doping presents a potential pathway to superconductivity in such materials.

Purpose of the Study:

• To investigate the emergence of superconductivity via skyrmion condensation in a doped quantum spin Hall insulator.
• To model and simulate the doping-induced transition to superconductivity.
• To explore novel routes to superconductivity beyond conventional mechanisms.

Main Methods:

• Development of a theoretical model suitable for large-scale simulations.
• Application of negative sign-free quantum Monte Carlo simulations.
• Analysis of the doping-induced phase transition at high resolution (down to δ=0.0017).

Main Results:

• Evidence supporting a direct and continuous doping-induced transition.
• Observation of a transition from a quantum spin Hall insulator to an s-wave superconductor.
• Successful simulation of low-doping regimes.

Conclusions:

• Skyrmion condensation offers a viable route to induce superconductivity in quantum spin Hall insulators.
• The findings provide a theoretical framework for realizing superconductivity through doping.
• This work contributes to the ongoing search for novel superconducting states, similar to those explored in twisted bilayer graphene.