Transistor size is constantly being reduced to improve performance as well as power consumption. For the channel length to be reduced, the corresponding gate dielectric thickness should also be reduced. Unfortunately,...Transistor size is constantly being reduced to improve performance as well as power consumption. For the channel length to be reduced, the corresponding gate dielectric thickness should also be reduced. Unfortunately, graphene devices are more complicated due to an extra capacitance called quantum capacitance （CQ） which limits the effective gate dielectric reduction. In this work, we analyzed the effect of CQ on device-scaling issues by extracting it from scaling of the channel length of devices. In contrast to previous reports for metal-insulator- metal structures, a practical device structure was used in conjunction with direct radio-frequency field-effect transistor measurements to describe the graphene channels. In order to precisely extract device parameters, we reassessed the equivalent circuit, and concluded that the on-state model should in fact be used. By careful consideration of the underlap region, our device modeling was shown to be in good agreement with the experimental data. CQ contributions to equivalent oxide thickness were analyzed in detail for varying impurity concentrations in graphene. Finally, we were able to demonstrate that despite contributions from CQ, graphene＇s high mobility and low-voltage operation allows for ~raphene channels suitable for next generation transistors.展开更多
The new particle around 125 GeV observed at the LHC is almost consistent with the standard model Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. We propose to...The new particle around 125 GeV observed at the LHC is almost consistent with the standard model Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. We propose to use the vector-boson fusion to test the underlying model for electroweak symmetry breaking. Using the well known dijet-tagging technique to single out the vector-boson fusion mechanism, we investigate potential of vector-boson fusion to discriminate a number of models suggested to give an enhanced inclusive diphoton production rate.展开更多
Extraordinary electronic properties can emerge at the interfaces between metal oxides[1-10].Interfacial behaviors have enabled a wide range of applications from electronic communication,energy conversion and storage,t...Extraordinary electronic properties can emerge at the interfaces between metal oxides[1-10].Interfacial behaviors have enabled a wide range of applications from electronic communication,energy conversion and storage,to data processing and memory.In recent years,unprecedented progress has been made in exploring and exploiting the emergent and/or enhanced properties of these interfaces,and it is becoming clear that interface engineering provides a new opportunity for advanced devices in the near future.The capability of using interfaces to manipulate material properties offers an effective means to achieve intriguing phenomena.展开更多
文摘Transistor size is constantly being reduced to improve performance as well as power consumption. For the channel length to be reduced, the corresponding gate dielectric thickness should also be reduced. Unfortunately, graphene devices are more complicated due to an extra capacitance called quantum capacitance （CQ） which limits the effective gate dielectric reduction. In this work, we analyzed the effect of CQ on device-scaling issues by extracting it from scaling of the channel length of devices. In contrast to previous reports for metal-insulator- metal structures, a practical device structure was used in conjunction with direct radio-frequency field-effect transistor measurements to describe the graphene channels. In order to precisely extract device parameters, we reassessed the equivalent circuit, and concluded that the on-state model should in fact be used. By careful consideration of the underlap region, our device modeling was shown to be in good agreement with the experimental data. CQ contributions to equivalent oxide thickness were analyzed in detail for varying impurity concentrations in graphene. Finally, we were able to demonstrate that despite contributions from CQ, graphene＇s high mobility and low-voltage operation allows for ~raphene channels suitable for next generation transistors.
文摘The new particle around 125 GeV observed at the LHC is almost consistent with the standard model Higgs boson, except that the diphoton decay mode may be excessive. We summarize a number of possibilities. We propose to use the vector-boson fusion to test the underlying model for electroweak symmetry breaking. Using the well known dijet-tagging technique to single out the vector-boson fusion mechanism, we investigate potential of vector-boson fusion to discriminate a number of models suggested to give an enhanced inclusive diphoton production rate.
基金supported by the National Nature Science Foundation of China(U1530402,17N1041)the CINT User Program+2 种基金the support by the U.S.National Science Foundation(ECCS-1902623)the support by the National Nature Science Foundation of China(51728202)the Center for Nanoscale Materials,an Office of Science user facility,supported by the U.S.Department of Energy(DE-AC02-06CH11357)
文摘Extraordinary electronic properties can emerge at the interfaces between metal oxides[1-10].Interfacial behaviors have enabled a wide range of applications from electronic communication,energy conversion and storage,to data processing and memory.In recent years,unprecedented progress has been made in exploring and exploiting the emergent and/or enhanced properties of these interfaces,and it is becoming clear that interface engineering provides a new opportunity for advanced devices in the near future.The capability of using interfaces to manipulate material properties offers an effective means to achieve intriguing phenomena.
