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A biosensor based on graphene nanoribbon with nanopores:a first-principles devices-design

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Chinese Physics B 2011年第5期20卷 455-459页

作者：欧阳方平彭盛霖张华翁立波徐慧 School of Physics Science and Technology Central South University College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking University

A biosensor device, built from graphene nanoribbons （GNRs） with nanopores, was designed and studied by first- principles quantum transport simulation. We have demonstrated the intrinsic transport properties of the device and the effect of different nucleobases on device properties when they are located in the nanopores of GNRs. It was found that the device＇s current changes remarkably with the species of nucleobases, which originates from their different chemical compositions and coupling strengths with GNRs. In addition, our first-principles results clearly reveal that the distinguished ability of a device＇s current depends on the position of the pore to some extent. These results may present a new way to read off the nucleobases sequence of a single-stranded DNA （ssDNA） molecule by such GNRs-based device with designed nanopores

关键词： graphene nanoribbon nanopores DNA sequencing first-principles

Tunable nano Peltier cooling device from geometric effects using a single graphene nanoribbon

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Frontiers of physics 2014年第4期9卷 472-476页

作者： Wan-Ju Li Dao-Xin Yao E. W. Carlson Department of Physics Purdue University West Lafayette IN 47907 USA State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-Sen University Guangzhou 510275 China

Based on the phenomenon of curvature-induced doping in graphene we propose a class of Peltier cooling devices, produced by geometrical effects, without gating. We show how a graphene nanorib- bon laid on an array of curved nano cylinders can be used to create a targeted and tunable cooling device. Using two different approaches, the Nonequilibrium Green＇s Function （NEGF） method and experimental inputs, we predict that the cooling kW/cm2, on par with the best known techniques power of such a device can approach the order of using standard superlattice structures. The structure proposed here helps pave the way toward designing graphene electronics which use geometry rather than gating to control devices.

关键词： Peltier cooling device graphene nanoribbon superlattice structure grapheneelectronics cooling power Nonequilibrium Green's Function (NI3GE)

Inverse Stone-Thrower-Wales defect and transport properties of 9AGNR double-gate graphene nanoribbon FETs

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Journal of Central South University 2019年第11期26卷 2943-2952页

作者： Mohammad Bagher NASROLLAHNEJAD Parviz KESHAVARZI Electrical and Computer Engineering Department Semnan University

Defect-based engineering of carbon nanostructures is becoming an important and powerful method to modify the electron transport properties in graphene nanoribbon FETs. In this paper, the impact of the position and symmetry of the ISTW defect on the performance of low dimensional 9AGNR double-gate graphene nanoribbon FET (DG-GNRFET) is investigated. Analyzing the transmission spectra, density of states and current-voltage characteristics shows that the defect effect on the electron transport is considerably varied depending on the positions and the orientations (the symmetric and asymmetric configuration) of the ISTW defect in the channel length. Based on the results, the asymmetric ISTW defect leads to a more controllability of the gate voltages over drain current, and drain current increases more than 5 times. The results have also con rmed the ISTW defect engineering potential on controlling the channel electrical current of DG-AGNR FET.

关键词： inverse Stone-Thrower-Wales defect electronic transport properties graphene nanoribbon tight binding NEGF formalism

Comparison of tunneling currents in graphene nanoribbon tunnel field effect transistors calculated using Dirac-like equation and Schrodinger’s equation

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Journal of Semiconductors 2019年第6期40卷 43-47页

作者： Endi Suhendi Lilik Hasanah Dadi Rusdiana Fatimah A. Noor Neny Kurniasih Khairurrijal Physics of Electronic Material Research Division Universitas Pendidikan Indonesia Bandung 40154 Indonesia Physics of Electronic Material Research Division Institut Teknologi Bandung Bandung 40132 Indonesia Earth Physics and Physics of Complex Systems Research Division Institut Teknologi Bandung Bandung 40132 Indonesia

The tunneling current in a graphene nanoribbon tunnel field effect transistor(GNR-TFET) has been quantum mechanically modeled. The tunneling current in the GNR-TFET was compared based on calculations of the Dirac-like equation and Schrodinger’s equation. To calculate the electron transmittance, a numerical approach-namely the transfer matrix method(TMM)-was employed and the Launder formula was used to compute the tunneling current. The results suggest that the tunneling currents that were calculated using both equations have similar characteristics for the same parameters, even though they have different values. The tunneling currents that were calculated by applying the Dirac-like equation were lower than those calculated using Schrodinger’s equation.

关键词： graphene nanoribbon tunnel field effect transistor tunneling current Schrodinger equation Dirac-like equation

Steady-state property and dynamics in graphene-nanoribbon- array lasers

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Frontiers in Biology 2012年第5期7卷 527-532页

作者： Xing-Hai Zhao Guang-Cun Shan Chan-Hung Shek Institute of Electronic Engineering China Academy of Engineering PhysicsMianyang 621900China Department of Physics and Materials Science City University of Hong KongHong Kong SARChina

In this work, we present a schematic configuration and device model for a graphene-nanoribbon （GNR）-array-based nanolaser, which consists of a three-variable rate equations that takes into account carrier capture and Pauli blocking in semiconductor GNR-array lasers to analyze the steady- state properties and dynamics in terms of the role of the capture rate and the gain coefficient in GNR array nanolasers. Furthermore, our GNR-array nanolaser device model can be determined as two distinct two-variable reductions of the rate equations in the limit of large capture rates, depending on their relative values. The first case leads to the rate equations for quantum well lasers, exhibiting relaxation oscillations dynamics. The second case corresponds to GNRs nearly saturated by the carriers and is characterized by the absence of relaxation oscillations. Our results here demonstrated that GNR-array as gain material embedded into a high finesse microcavity can serve as an ultralow lasing threshold nanolaser with promising applications ranging widely from optical fiber communi- cation with increasing data processing speed to digital optical recording and biology spectroscopy.

关键词： graphene nanoribbon graphene nanoribbon laser laser theory laser model

Efficient Synthesis of graphene nanoribbons Sonochemically Cut from graphene Sheets

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Nano Research 2010年第1期3卷 16-22页

作者： Zhong-Shuai Wu Wencai Ren Libo Gao Bilu Liu Jinping Zhao Hui-Ming Cheng Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

We report a facile approach to synthesize narrow and long graphene nanoribbons (GNRs) by sonochemically cutting chemically derived graphene sheets (GSs). The yield of GNRs can reach ~5 wt% of the starting GSs. The resulting GNRs are several micrometers in length, with ~75% being single-layer, and ~40% being narrower than 20 nm in width. A chemical tailoring mechanism involving oxygen-unzipping of GSs under sonochemical conditions is proposed on the basis of experimental observations and previously reported theoretical calculations;it is suggested that the formation and distribution of line faults on graphite oxide and GSs play crucial roles in the formation of GNRs. These results open up the possibilities of the large-scale synthesis and various technological applications of GNRs.

关键词： graphene nanoribbon graphene oxide synthesis sonochemical cutting

Transport properties of zigzag graphene nanoribbons adsorbed with single iron atom

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Chinese Physics B 2015年第11期24卷 428-433页

作者：杨玉娥肖杨颜晓红戴昌杰 Department of Applied Physics Nanjing University of Aeronautics and Astronautics

We have performed density-functional calculations of the transport properties of the zigzag graphene nanoribbon （ZGNR） adsorbed with a single iron atom. Two adsorption configurations are considered, i.e., iron adsorbed on the edge and on the interior of the nanoribbon. The results show that the transport features of the two configurations are similar. However, the transport properties are modified due to the scattering effects induced by coupling of the ZGNR band states to the localized 3d-orbital state of the iron atom. More importantly, one can find that several dips appear in the transmission curve, which is closely related to the above mentioned coupling. We expect that our results will have potential applications in graphene-based spintronic devices,

关键词： graphene nanoribbon transport properties iron adatom

Modulated thermal transport for flexural and in-plane phonons in double-stub graphene nanoribbons

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Chinese Physics B 2018年第8期27卷 566-571页

作者： Chang-Ning Pan Meng-Qiu Long JuJa He Hunan Key Laboratory of Super Micro-structure and Ultrafast Process School of Physics and Electronics Central South UniversityChangsha 410083China School of Science Hunan University of TechnologyZhuzhou 412008China

Thermal transport properties are investigated for out-of-plane phonon modes （FPMs） and it-plane phonon modes （IPMs） in double-stub graphene nanoribbons （GNRs）. The results show that the quantized thermal conductance plateau of FPMs is narrower and more easily broken by the double-stub structure. In the straight GNRs, the thermal conductance of FPMs is higher in the low temperature region due to there being less cut-off frequency and more low-frequency excited modes. In contrast, the thermal conductance of IPMs is higher in the high temperature region becau~,＇.e of the wider phonon energy spectrum. Furthermore, the thermal transport of two types of phonon modes can be modulated by the double-stub GNRs, the thermal conductance of FPMs is less than that of IPMs in the low temperatures, but it dominates the contribution to the total thermal conductance in the high temperatures. The modulated thermal conclu~＇tanc：e can provide a guideline for designing high-performance thermal or thermoelectric nanodevices based on graphene.

关键词： graphene nanoribbon flexural phonons in-plane phonons thermoelectric properties

Electronic structures and transport properties of BN nanodot superlattices of armchair graphene nanoribbons

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Journal of Semiconductors 2011年第9期32卷 6-11页

作者：安丽萍刘念华 Institute for Advanced Study Nanchang University Department of Physics Yanshan University

The electronic and transport properties of embedded boron nitride（BN） nanodot superlattices of armchair graphene nanoribbons are studied by first-principles *** band structure of the graphene superlattice strongly depends on the geometric shape and size of the BN nanodot,as well as the concentration of *** conduction bands and valence bands near the Fermi level are nearly symmetric,which is induced by electron-hole *** B and N atoms in the graphene superlattices with a triangular BN nanodot are exchanged,the valance bands and conduction bands are inverted with respect to the Fermi level due to electron-hole *** addition,the hybridization ofπorbitals from C and redundant B atoms or N atoms leads to a localized band appearing near the Fermi *** results also show a series of resonant peaks appearing in the *** strongly depends on the distance of the two BN nanodots and on the shape of the BN nanodot. Controlling these parameters might allow the modulation of the electronic response of the systems.

关键词： graphene nanoribbon BN nanodot electronic properties transport properties