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08:12
Ohmic Contact Fabrication Using a Focused-ion Beam Technique and Electrical Characterization for Layer Semiconductor Nanostructures
Published on: December 5, 2015
Topological superconductivity in monolayer transition metal dichalcogenides
Yi-Ting Hsu1, Abolhassan Vaezi2, Mark H Fischer3
1Department of Physics, Cornell University, Ithaca, New York 14853, USA.
Nature Communications
|April 12, 2017
Summary
Researchers propose realizing spinless fermions in hole-doped transition metal dichalcogenides (TMDs) to create rare topological superconductors. This approach utilizes momentum-space spin splitting for potential device applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Computing
Background:
- Topological superconductors are rare, despite theoretical promise for applications.
- Breaking spin degeneracy to achieve spinless fermions is a key theoretical pathway.
- Existing superconducting transition metal dichalcogenides (TMDs) are typically electron-doped and unlikely topological.
Purpose of the Study:
- To propose a novel mechanism for realizing spinless fermions.
- To identify candidate materials for topological superconductivity.
- To explore the potential of hole-doped transition metal dichalcogenides (TMDs).
Main Methods:
- Theoretical proposal utilizing momentum-space spin splitting.
- Renormalization group analysis of interacting spinless fermions.
- Identification of monolayer hole-doped TMDs as promising candidates.
Main Results:
- Hole-doped TMDs exhibit momentum-space split spinless fermions due to unusual spin-valley locking.
- Repulsive interactions favor two specific topological superconducting states.
- Predicted states include an interpocket paired state (Chern number 2) and an intrapocket paired state.
Conclusions:
- Hole-doped TMDs offer a viable platform for realizing topological superconductivity.
- The proposed mechanism overcomes limitations of electron-doped TMDs.
- Experimental confirmation could enable device applications of topological superconductors.
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