Enhanced Thermionic-Dominated Photoresponse in Graphene Schottky Junctions

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Vertical heterostructures of van der Waals materials offer advanced control over nanoscale charge and energy transport.
• Graphene-based devices are crucial for developing next-generation electronic and optoelectronic applications.

Purpose of the Study:

• To propose and theoretically investigate a unique photoresponse regime in graphene Schottky junctions.
• To explore the potential for efficient vertical energy extraction via coupled heat and charge flows.

Main Methods:

• Theoretical modeling of charge and energy transport in graphene Schottky junctions.
• Analysis of thermionic emission of hot carriers and electron-lattice cooling dynamics.
• Investigation of the conditions for vertical energy transport dominance.

Main Results:

• A novel photoresponse characterized by strongly coupled vertical heat and charge flows is proposed.
• Efficient power extraction across the graphene active area via thermionic emission is demonstrated.
• A large, tunable internal responsivity with nonmonotonic temperature dependence is predicted, peaking at specific electronic temperatures.

Conclusions:

• The proposed regime offers a new pathway for engineering photoresponse in optically active graphene heterostructures.
• This work highlights the potential of graphene Schottky junctions for advanced photodetector applications.
• Efficient vertical energy transport via hot carrier thermionic emission is key to achieving high responsivity.