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Abstract We study the transport properties of mm-scale CVD graphene p-n junctions, which are formed in a single gated graphene field effect transistor configuration. Here, an electrical-stressing-voltage technique served to modify the electrostatic potential in the SiO2/Si substrate and create the p-n junction. We examine the transport characteristics about the Dirac points that are localized in the perturbed and unperturbed regions in the graphene channel and note the quantitative differences in the Hall effect between the perturbed and unperturbed regions. The results also show that the longitudinal resistance is highly sensitive to the external magnetic field when the Hall bar device operates as a p-n junction.
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Pyroelectric gating of graphene transistor for plasmon-enhanced optical sensing
A plasmon-enhanced pyroelectric membrane was applied to control the current flow in a graphene transistor for light detection. The graphene transistor was built on a free-standing, 15-μm-thick PVDF membrane, which was doped using gold nanorods to facilitate its optical absorption. Under the resonant condition, the device exhibited a responsivity of 0.79 μA/mW.
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- Award ID(s):
- 1653673
- PAR ID:
- 10402490
- Date Published:
- Journal Name:
- CLEO: Applications and Technology
- Page Range / eLocation ID:
- JTh3A.66
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Cation–π interactions between molecules and graphene are known to have a profound effect on the properties of the molecule/graphene nanohybrids and motivate this study to quantify the attachment of the rhodamine 6G (R6G) dye molecules on graphene and the photocarrier transfer channel formed across the R6G/graphene interface. By increasing the R6G areal density of the R6G on graphene field‐effect transistor (GFET) from 0 up to ≈3.6 × 1013cm−2, a linear shift of the Dirac point of the graphene from originally 1.2 V (p‐doped) to −1 V (n‐doped) is revealed with increasing number of R6G molecules. This indicates that the attachment of the R6G molecules on graphene is determined by the cation–π interaction between the NH+ in R6G and π electrons in graphene. Furthermore, a linear dependence of the photoresponse on the R6G molecule concentration to 550 nm illumination is observed on the R6G/graphene nanohybrid, suggesting that the cation–π interaction controls the R6G attachment configuration to graphene to allow formation of identical photocarrier transfer channels. On R6G/graphene nanohybrid with 7.2 × 107R6G molecules, high responsivity up to 5.15 × 102A W−1is obtained, suggesting molecule/graphene nanohybrids are promising for high‐performance optoelectronics.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1364/CLEO_AT.2022.JTh3A.66
