Graphene nanoribbons (GNRs) with widths down to 16 nm have been characterized for their currentcarrying capacity. It is found that GNRs exhibit an impressive breakdown current density, on the order of 10 8 A/cm 2 . The breakdown current density is found to have a reciprocal relationship to GNR resistivity and the data fit points to Joule heating as the likely mechanism of breakdown. The superior current-carrying capacity of GNRs will be valuable for their application in on-chip electrical interconnects. The thermal conductivity of sub-20 nm graphene ribbons is found to be more than 1000 W/m-K.Keywords: Graphene, Breakdown current density, Nano ribbons, Maximum current * raghu@gatech.edu, Ph: 404 385 6463 2 Graphene is a promising electronic material because of many interesting properties like ballistic transport 1 , high intrinsic mobility 2 , and width-dependent bandgap 3 . Graphene, in its 2D form, has been shown to have a high thermal conductivity 4 of around 5000 W/m-K pointing to its potential use as an on-chip heat spreader.Graphene nano ribbons (GNRs) have been predicted to be superior to Cu in terms of resistance per unit length 5 for use as on-chip interconnects. A high current-carrying capacity is critical for interconnect applications and reliability. There have been a number of studies on carbon nanotube (CNT) breakdown current density, and the current-carrying capacity of single-walled CNTs 6 is found to be on the order of 10 8 A/cm 2 ; in carbon nanofibers, the breakdown current density (J BR ) has been measured 7 to be around 5x10 6 A/cm 2 . Electrical breakdown has been used to burn away successive shells in a multi-wall CNT 8,9 . More recently, electrical breakdown has been used to obtain semiconducting CNTs from a mixture of CNTs since metallic ones burn away at a lower breakdown voltage 10 . Theoretical projections suggest that J BR of graphene should be on the same order as for CNTs. However, little experimental evidence exists on the electrical breakdown of either 2D graphene or 1D GNRs. In this work, it is experimentally shown that GNRs demonstrate an impressive J BR . A simple relation between J BR and nanowire resistivity is seen to emerge from the experimental data.Few-layer graphene (1-5 layers) is used as the starting material (see supporting material 11 ).Each device consists of parallel ribbons fabricated between sets of electrodes, Fig. 1. The ribbon width between a pair of electrodes is designed to be the same for all the parallel ribbons. The range of widths studied in this work is 16nm

The localized surface plasmon resonance (LSPR) spectral band of a gold or silver nanoparticle is observed to shift as a result of the near-field plasmonic field of another nanoparticle. The dependence of the observed shift on the interparticle distance is used as a ruler in biological systems and gave rise to a plasmonic ruler equation in which the fractional shift in the dipole resonance is found to decrease near exponentially with the interparticle separation in units of the particle size. The exponential decay length constant was observed to be consistent among a small range of nanoparticle sizes, shapes, and types of metal. The equation was derived from the observed results on disks and spherical nanoparticles and confirmed using results on a DNA conjugated nanosphere system. The aim of the present paper is to use electron beam lithography and DDA calculations to examine the constancy of the exponential decay length value in the plasmonic ruler equation on particle size and shape of a number of particles including nanoparticles of different symmetry and orientations. The results suggest that the exponent is almost independent of the size of the nanoparticle but very sensitive to the shape. A discussion of the nanoparticles most suitable for different applications in biological systems and a comparison of the plasmonic ruler with Forster resonance energy transfer (FRET) is mentioned.

Abstract-Graphene nanoribbon interconnects are fabricated, and the extracted resistivity is compared to that of Cu. It is found that the average resistivity at a given line-width (18nm

We report on the binding mechanisms of oxygen and water to graphene by comparing the doping of graphene in a dry O2 environment versus in ambient. It is seen that dry oxygen dopes graphene from the basal plane while the ambient dopes graphene from the edges or from the substrate in the vicinity of the edge. Upon vacuum annealing, doping is fully reversible in the former case and only partially reversible in the latter case. We observe a thickness-dependent doping as a result of the difference in host sites for doping (basal plane versus edge). Finally, hysteresis is shown to be triggered even in dry oxygen.

A single-step doping method capable of high resolution n- and p-type doping of large area graphene is presented. Thin films of hydrogen silsesquoxane on exfoliated graphene are used to demonstrate both electron and hole doping through control of the polymer cross-linking process. This dual-doping is attributed to the mismatch in bond strength of the Si–H and Si–O bonds in the film as well as out-gassing of hydrogen with increasing cross-linking. A high-resolution graphene p-n junction is demonstrated using this method.

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We report on experimental evidence of directed electron transport, induced by external linear-polarized microwave irradiation, in a two-dimensional spatially-periodic asymmetrical system called "ratchet". The broken spatial symmetry was introduced in a high mobility two-dimensional electron gas based on AlGaAs/GaAs heterojunction, by patterning an array of artificial semi-discs-shaped antidots. We show that the direction of the transport is efficiently changed by microwave polarization. The dependence of the effect on magnetic field and temperature is investigated. This represents a significant step towards the realization of new microwave detectors and current generators.

Graphene has shown impressive properties for nanoelectronics applications including a high mobility and a width-dependent bandgap. Use of graphene in nanoelectronics would most likey be in the form of graphene nanoribbons (GNRs) where the ribbon width is expected to be less than 20 nm. Many theoretical projections have been made on the impact of edge-scattering on carrier transport in GNRs - most studies point to a degradation of mobility (of GNRs) as well as the on/off ratio (of GNR FETs). This study provides the first clear experimental evidence of the onset of size-effect in patterned GNRs; it is shown that for W<60 nm, carrier mobility in GNRs is limited by edge-scattering.Comment: to be published in IEEE Electron Device Letter