Frequency-dependent quantum capacitance and plasma wave in monolayer transition metal dichalcogenides

Journal Article · Mon Mar 10 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4868432· OSTI ID:22257047

Lam, Kai-Tak; Guo, Jing ^[1]

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1. Department of Electrical and Computer Engineering, University of Florida, Gainesville, Florida 32611 (United States)

Frequency-dependent quantum capacitance C{sub Q} of monolayer transition metal dichalcogenides (TMDs) is computed and compared to that of graphene. It is found that the frequency dependence of C{sub Q} in TMDs differs drastically from that of graphene which has a divergent point. The plasma resonance forms when the quantum capacitance is negative and has the same magnitude as the electrostatic capacitance. The calculation shows that the plasma in TMDs depends on the band-structure-limited velocity, band gap, and doping density, which can be controlled via gate biases. The plasma frequencies of TMDs are in the rage of terahertz useful for various applications.

• OSTI ID: 22257047
• Journal Information: Applied Physics Letters, Vol. 104, Issue 10; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CAPACITANCE
FREQUENCY DEPENDENCE
GRAPHENE
LANGMUIR FREQUENCY
PLASMA WAVES
RESONANCE
TRANSITION ELEMENTS