Effect of the edge states on the conductance and thermopower in Zigzag Phosphorene Nanoribbons

Abstract

We numerically study the effect of the edge states on the conductance and thermopower in zigzag phosphorene nanoribbons (ZPNRs) based on the tight-binding model and the scattering-matrix method. It is interesting to find that the band dispersion, conductance, and thermopower can be modulated by applying a bias voltage and boundary potentials to the two layers of the ZPNRs. Under the certain bias voltage, the two-fold degenerate quasi-flat edge bands split perfectly. The conductance can be switched off, and the thermopower around zero energy increases. In addition, when only the boundary potential of the top layer or bottom layer is adjusted, only one edge band bends and merges into the bulk band. The first conductance plateau is strongly decreased to $e^2/h$ around zero energy. Particularly, when the two boundary potentials are adjusted, all the edge bands bend and fully merge into the bulk band, and the bulk energy gap is maximized. More interestingly, a pronounced conductance plateau with $G=0$ is found around zero energy, which is attributable to the opening of the bulk energy gap between the valence and conduction bands. Meanwhile, the thermopower can be enhanced more than twice, compared to that of the perfect ZPNRs. The large magnitude of thermopower is ascribed to the appearance of the bulk energy gap around zero energy. Our results show that the modulated ZPNRs are more reliable in thermoelectric application.

arXiv comment6 pages, 6 figures

References in corpus (29)

• Atomically thin MoS2: A new direct-gap semiconductor
• Black phosphorus field-effect transistors
• Phosphorene: A New 2D Material with High Carrier Mobility
• High-mobility transport anisotropy and linear dichroism in few-layer black phosphorus
• Rediscovering Black Phosphorus: A Unique Anisotropic 2D Material for Optoelectronics and Electronics
• Isolation and characterization of few-layer black phosphorus
• Kwant: a software package for quantum transport
• Electric field effect in ultrathin black phosphorus
• Enhanced Thermoelectric Efficiency via Orthogonal Electrical and Thermal Conductances in Phosphorene
• Quasiparticle band structure and tight-binding model for single- and bilayer black phosphorus
• Phosphorene nanoribbons, nanotubes and van der Waals multilayers
• Quantum Hall Effect in Black Phosphorus Two-dimensional Electron Gas
• Edge states in Graphene: from gapped flat band to gapless chiral modes
• Enhanced thermoelectric performance of phosphorene by strain-induced band convergence
• Phosphorene nanoribbon as a promising candidate for thermoelectric applications
• Unusual Scaling Laws of the Band Gap and Optical Absorption of Phosphorene Nanoribbons
• Electrically Tunable Quasi-Flat Bands, Conductance and Field Effect Transistor in Phosphorene
• Hinge-like structure induced unusual properties of black phosphorus and new strategies to improve the thermoelectric performance
• Phosphorene nanoribbons
• Thermoelectric power of bulk black-phosphorus
• Scaling laws for band gaps of phosphorene nanoribbons: A tight-binding calculation
• MoS2 nanoribbons as promising thermoelectric materials
• Enhanced Thermoelectric Power in Dual-Gated Bilayer Graphene
• Nernst and Seebeck effect in a graphene nanoribbon
• Thermopower of gapped bilayer graphene
• Universal Thermoelectric Effect of Dirac Fermions in Graphene
• Tunable skewed edges in puckered structures
• Thermoelectric and thermal transport in bilayer graphene systems
• Stacking-order dependence in thermoelectric transport of biased trilayer graphene

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