Photovoltage oscillations in encapsulated graphene

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Electronics

Background:

• Hexagonal boron-nitride (h-BN) encapsulated monolayer graphene exhibits unique electronic properties.
• Terahertz (THz) radiation can induce interesting phenomena in 2D materials.
• Understanding photovoltage generation is crucial for optoelectronic applications.

Purpose of the Study:

• To theoretically investigate the emergence of photovoltage oscillations in h-BN/graphene/h-BN systems under THz irradiation.
• To explore the influence of applied voltages on these oscillations.
• To analyze the frequency dependence of the photovoltage response.

Main Methods:

• Utilized an extended radiation-driven electron orbit model, adapted for massive Dirac fermions.
• Performed theoretical simulations of photovoltage generation in graphene systems.
• Investigated the effects of vertical gate voltage and external side voltage.

Main Results:

• Observed significant photovoltage oscillations in the terahertz range, analogous to semiconductor magnetoresistance oscillations.
• Demonstrated that vertical gate voltage controls carrier effective mass.
• Showed that external voltage modulates photovoltage intensity and oscillation amplitude.

Conclusions:

• The study provides a theoretical framework for understanding THz-induced photovoltage oscillations in graphene.
• Applied voltages offer a mechanism to tune and control these oscillations.
• The findings are relevant for developing novel THz optoelectronic devices based on graphene.