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Excited state spectroscopy and spin splitting in single layer MoS2 quantum dots
P Kumar1,2, H Kim3, S Tripathy3
1Institute for Functional Intelligent Materials, National University of Singapore, Singapore, 117544, Singapore.
Nanoscale
|November 3, 2023
Summary
Researchers developed small quantum dots in molybdenum disulfide (MoS2) for quantum computing. They accurately measured the g-factor, a key property for spin qubits, paving the way for advanced quantum technologies in 2D materials.
Area of Science:
- Condensed Matter Physics
- Quantum Information Science
- Materials Science
Background:
- Semiconducting transition metal dichalcogenides (TMDCs) are promising for quantum dots and spin qubits.
- Accurate measurement of the Landé g-factor is crucial for reliable spin qubit operation.
- Existing TMDC quantum dots lack the size and control for precise g-factor measurements.
Purpose of the Study:
- To engineer and characterize quantum dots in single-layer MoS2 for quantum information applications.
- To enable reliable measurement of the Landé g-factor in atomically thin TMDC quantum dots.
- To establish a platform for evaluating spin-valley qubits in 2D materials.
Main Methods:
- Fabrication of quantum dots in single-layer MoS2 using a dual-gate geometry.
- Electron transport measurements to probe discrete energy levels.
- Magnetic field application to observe spin-filling sequences and measure the g-factor.
Main Results:
- Observation of quantum dots with discrete energy levels separated by 5-6 meV in single-layer MoS2.
- Accurate measurement of the ground state Landé g-factor as approximately 5.
- Demonstration of a spin-filling sequence under a perpendicular magnetic field.
Conclusions:
- Single-layer MoS2 quantum dots with well-resolved energy levels are achievable.
- The measured g-factor provides critical data for spin qubit development in TMDCs.
- This system serves as a valuable testbed for advancing spin-valley qubit technologies in 2D materials.
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