MDPI - Publisher of Open Access Journals

10 pages, 5201 KiB

Open AccessArticle

Band Structure and Quantum Transport of Bent Bilayer Graphene

by Xue Wang and Lei Xu

Materials 2022, 15(23), 8664; https://doi.org/10.3390/ma15238664 - 5 Dec 2022

Cited by 1 | Viewed by 1499

We investigate the band structures and transport properties of a zigzag-edged bent bilayer graphene nanoribbon under a uniform perpendicular magnetic field. Due to its unique geometry, the edge and interface states can be controlled by an electric field or local potential, and the conductance exhibits interesting quantized behavior. When Zeeman splitting is considered, the edge states are spin-filtered, and a weak quantum spin Hall (WQSH) phase appears. In the presence of an electric field or local potential, a WQSH-QH junction or WQSH-spin-unbalanced QSH junction can be achieved, respectively, while fully spin-polarized currents appear in the interface region. Zeeman splitting lifts the spin degeneracy, leading to a WQSH around zero energy with a quantized two-terminal conductance of 4e²/h, which is robust against weak nonmagnetic disorder. These results provide a way to manipulate the band structures and transport properties of the system using an electric field, local potential, and Zeeman splitting. Full article

(This article belongs to the Topic Advances and Applications of 2D Materials, 2nd Volume)

► Show Figures

Figure 1

15 pages, 6953 KiB

Open AccessEditor’s ChoiceLetter

Design of Flexible Pressure Sensor Based on Conical Microstructure PDMS-Bilayer Graphene

by Lixia Cheng, Renxin Wang, Xiaojian Hao and Guochang Liu

Sensors 2021, 21(1), 289; https://doi.org/10.3390/s21010289 - 4 Jan 2021

Cited by 44 | Viewed by 5896

Abstract

As a new material, graphene shows excellent properties in mechanics, electricity, optics, and so on, which makes it widely concerned by people. At present, it is difficult for graphene pressure sensor to meet both high sensitivity and large pressure detection range at the same time. Therefore, it is highly desirable to produce flexible pressure sensors with sufficient sensitivity in a wide working range and with simple process. Herein, a relatively high flexible pressure sensor based on piezoresistivity is presented by combining the conical microstructure polydimethylsiloxane (PDMS) with bilayer graphene together. The piezoresistive material (bilayer graphene) attached to the flexible substrate can convert the local deformation caused by the vertical force into the change of resistance. Results show that the pressure sensor based on conical microstructure PDMS-bilayer graphene can operate at a pressure range of 20 kPa while maintaining a sensitivity of 0.122 ± 0.002 kPa⁻¹ (0–5 kPa) and 0.077 ± 0.002 kPa⁻¹ (5–20 kPa), respectively. The response time of the sensor is about 70 ms. In addition to the high sensitivity of the pressure sensor, it also has excellent reproducibility at different pressure and temperature. The pressure sensor based on conical microstructure PDMS-bilayer graphene can sense the motion of joint well when the index finger is bent, which makes it possible to be applied in electronic skin, flexible electronic devices, and other fields. Full article

(This article belongs to the Section Sensor Materials)

► Show Figures

Figure 1

Search Results (2)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI

Saved Queries

Search Filter Reset All

Years

Feature Papers

Subjects

Journals

Article Types

Countries / Regions

Search Results (2)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI