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Updated: Jan 12, 2026
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Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
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Intercalation-induced staging superstructures in KxNbSe2
Qiwei Wang1, Ying-Jie Li1, Xuan Du1
1National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Jiangsu Physical Science Research Center, School of Physics, Nanjing University, Nanjing 210093, People's Republic of China.
Summary
We intercalated potassium into niobium diselenide (NbSe2) single crystals, creating superstructures that lead to stepwise superconductivity transitions. This reveals how atomic intercalation impacts material properties at the nanoscale.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Atomic intercalation is a key method for tuning physical properties in layered van der Waals materials.
- Understanding the structural evolution during intercalation, especially at the microscopic level, remains a challenge.
Purpose of the Study:
- To investigate the structural changes and resulting superconducting properties of potassium-intercalated 2H-niobium diselenide (KxNbSe2).
- To provide direct evidence of intercalation-induced superstructures and their effect on superconductivity.
Main Methods:
- Fabrication of KxNbSe2 samples using a liquid ammonia method for intercalating potassium (K) into 2H-NbSe2 single crystals.
- Characterization using X-ray diffraction (XRD) and transmission electron microscopy (TEM) to analyze structural evolution and superstructures.
Main Results:
- Formation of superstructures in KxNbSe2, well-described by a staging model with periods up to ~50 nm.
- Observation of stepwise superconductivity transitions correlating with the intercalation-induced superstructures.
Conclusions:
- Direct evidence of intercalation-induced superstructures in KxNbSe2 was established.
- The study demonstrates a direct link between structural superlattices and stepwise superconducting transitions in intercalated van der Waals materials.
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