Charge Transfer Dynamics in WS₂/NiPS₃ Heterostructures

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Magnetic van der Waals (vdW) heterostructures (HSs) offer tunable charge and spin transfer via interface engineering.
• Understanding the dynamics of interfacial phenomena in these systems is critical but requires further investigation.

Purpose of the Study:

• To investigate the interfacial charge transfer dynamics in a specific vdW HS.
• To explore the role of d-orbital localization in magnetic materials within these heterostructures.

Main Methods:

• Fabrication of a heterostructure comprising layered antiferromagnetic NiPS₃ and transition metal dichalcogenide WS₂.
• Resonant excitation of WS₂ to probe interfacial charge transfer dynamics.
• Spectroscopic analysis to observe d-d transitions and trion emissions.

Main Results:

• Observed enhanced d-d transition in NiPS₃ due to charge transfer from WS₂ to Ni 3d orbitals.
• Detected anomalous enhancement of trion emission in WS₂.
• Measured a slow (∼23 ps) charge transfer from NiPS₃ to WS₂, linked to localized Ni 3d orbitals.

Conclusions:

• The study highlights the significant localization property of d-orbitals in magnetic materials.
• Provides crucial insights into the interfacial dynamics of magnetic vdW HS.
• Findings are fundamental for the design of novel electronic devices utilizing magnetic vdW HS.