Quantum inductance and high frequency oscillators in graphene nanoribbons

Area of Science:

• Condensed matter physics
• Materials science
• Nanotechnology

Background:

• Graphene nanoribbons (GNRs) are promising materials for electronic devices.
• Quantum dots (QDs) exhibit unique electronic properties.
• Understanding high-frequency AC transport in nanostructures is crucial for advanced electronics.

Purpose of the Study:

• To investigate high-frequency AC transport in graphene nanoribbons with top-gate defined quantum dots.
• To determine the effective electrical behavior of these devices at GHz frequencies.
• To explore their potential applications in high-frequency electronics.

Main Methods:

• Fabrication of narrow graphene nanoribbons with top-gate potentials.
• Measurement of AC transport properties at high frequencies (≥ GHz).
• Modeling of device admittance considering geometric and quantum capacitance.

Main Results:

• The quantum dot in the graphene nanoribbon exhibits classical inductor behavior at high frequencies due to finite electron dwell time.
• The device admittance mimics a classical serial RLC circuit.
• Observed resonant frequencies in the 100-900 GHz range with high Q-factors (> 10^6).

Conclusions:

• Graphene nanoribbons with quantum dots can function as all-electronic ultra-high frequency oscillators and filters.
• These findings extend the application domain of high-frequency electronics.
• Graphene nanoribbons offer a novel platform for THz-range electronic components.