Interfacial Charge Transfer and Gate-Induced Hysteresis in Monochalcogenide InSe/GaSe Heterostructures

Area of Science:

• Materials Science: Focuses on two-dimensional (2D) van der Waals heterostructures.
• Condensed Matter Physics: Investigates electronic transport phenomena in novel semiconductor materials.

Background:

• Two-dimensional (2D) van der Waals semiconductor heterostructures are promising for fundamental physics and device applications.
• Indium selenide (InSe) and gallium selenide (GaSe) are 2D monochalcogenide materials with potential for unique electronic properties.

Purpose of the Study:

• To investigate the electronic transport properties of InSe/GaSe heterostructures.
• To understand the role of charge transfer and hysteresis in the device performance of these 2D van der Waals materials.

Main Methods:

• Fabrication of InSe/GaSe heterostructures using sequential mechanical exfoliation and stacking.
• Electrical characterization of the heterostructures, including gate voltage-dependent transport measurements.
• Analysis of conductance decay rates and hysteresis effects in electron transport.

Main Results:

• Observed significant charge transfer between InSe and GaSe layers due to 2D van der Waals interface formation.
• Detected a strong hysteresis effect in electron transport through the InSe layer, modulated by gate voltage applied via the GaSe layer.
• Found a gate voltage-dependent conductance decay rate, linked to dynamical charge transfer between the stacked layers.

Conclusions:

• The observed electronic transport phenomena in InSe/GaSe heterostructures are attributed to gate voltage-dependent dynamical charge transfer.
• These findings highlight the complex interplay between charge transfer and electronic transport in 2D van der Waals heterostructures.
• Understanding these effects is crucial for the development of novel electronic devices based on InSe/GaSe and similar 2D materials.