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Spin-Stabilization by Coulomb Blockade in a Vanadium Dimer in WSe2
Samuel Stolz1,2, Bowen Hou3, Dan Wang3
1nanotech@surfaces Laboratory, Empa - Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland.
ACS Nano
|November 17, 2023
Summary
Charged vanadium dopants in tungsten diselenide (WSe2) form unique electronic states and magnetism. Interactions between dopant pairs, influenced by charge transfer, control their magnetic properties in 2D materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Surface Science
Background:
- Charged dopants in 2D transition metal dichalcogenides (TMDs) influence electronic properties, forming hydrogenic states and magnetism.
- Charge transfer at interfaces and proximity to defects regulate dopant energy levels.
Purpose of the Study:
- Investigate vanadium-doped WSe2 monolayers on epitaxial graphene.
- Understand charge stabilization and many-body effects in single dopants and dopant pairs.
Main Methods:
- High-resolution scanning probe microscopy
- Ab initio calculations
Main Results:
- Vanadium substitutes W atoms (V_W) and becomes negatively charged via charge donation from graphene.
- V_W^-1 dopants show p-type defect states and hydrogenic states.
- V dimers exhibit charge-state dependent magnetism; nearest-neighbor dimers show paramagnetic ground states due to Coulomb blockade.
Conclusions:
- Charge transfer from graphene stabilizes V dopants in WSe2.
- Dopant-dopant interactions, particularly in dimers, significantly impact electronic and magnetic properties.
- Findings offer insights into controlling dopant behavior in 2D materials.
Keywords:
2D materialsDensity functional theoryPoint defectsScanning probe microscopyTransition metal dichalcogenideMore Related Videos
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