The proper understanding of semiconductor devices begins at the metal-semiconductor interface. metal/semiconductor interface itself can also be an important device, as Schottky junctions often forms when doping in semiconductors is low. Here, we extend analysis metal-silicon by using graphene, atomically thin semimetal. We show that a fundamentally new transport model needed to describe graphene-silicon junction. While current-voltage behavior follows celebrated ideal diode behavior, details...

We demonstrate that individual single-walled carbon nanotubes (SWNTs) can form ideal p-n junction diodes. An behavior is the theoretical limit of performance for any diode, a highly sought after goal in all electronic materials development. further elaborate on their properties by examining photovoltaic effects, an application where its intimately related to quality diode. Under illumination, SWNT diodes show significant power conversion efficiencies owing enhanced

We demonstrate a single-walled carbon nanotube p-n junction diode device. The is formed along single by electrostatic doping using pair of split gate electrodes. By biasing the two gates accordingly, device can function either as or an ambipolar field-effect transistor. current–voltage characteristics show forward conduction and reverse blocking characteristics, i.e., rectification. For low bias conditions, follow ideal equation with ideality factor close to one.

We find that optical second-harmonic generation (SHG) in reflection from a chemical-vapor-deposition graphene monolayer transferred onto SiO2/Si(001) substrate is enhanced about 3 times by the flow of direct current electric graphene. Measurements rotational-anisotropy SHG revealed current-induced current-biased graphene/SiO2/Si(001) structure undergoes phase inversion as measurement location on shifted laterally along direction. The enhancement due to current-associated charge trapping at...

The field of plasmonics relies on light coupling strongly to plasmons as collective excitations. energy loss function graphene is dominated by two peaks at ∼5 and ∼15 eV, known π + σ plasmons, respectively. We use electron energy-loss spectroscopy in an aberration-corrected scanning transmission microscope density functional theory show that between 1 50 these prominent are not but single-particle interband

We find that the flow of direct electric current (dc) through graphene on substrate enhances surface optical second-harmonic generation (SHG) from graphene/substrate system. The can enhance SHG by about 300% for a chemical-vapor-deposition (CVD) monolayer SiO${}_{2}/\mathrm{Si}(001)$ substrate, and 25% an epitaxial four-layer-graphene film 3.5\ifmmode^\circ\else\textdegree\fi{}-miscut vicinal SiC(0001) substrate. enhancement in both CVD samples is due to field-induced SHG, which produced...

Abstract Metal–semiconductor interfaces, known as Schottky junctions, have long been hindered by defects and impurities. Such imperfections dominate the electrical characteristics of junction pinning metal Fermi energy. Here, a graphene–WSe 2 p‐type junction, which exhibits lack level pinning, is studied. The displays near‐ideal diode with large gate tunability small leakage currents. Using electrostatically coupled to WSe channel tune barrier height, Schottky–Mott limit probed in single...

Realizing basic semiconductor devices such as p-n junctions are necessary for developing thin-film and optoelectronic technologies in emerging planar materials MoS2. In this work, electrostatic doping by buried gates is used to study the electronic properties of exfoliated MoS2 flakes. Creating a controllable gradient across device leads observation photovoltaic effect monolayer bilayer For thicker flakes, strong ambipolar conduction enables realization fully reconfigurable junction diodes...

In the development of semiconductor devices, bipolar junction transistor (BJT) features prominently as being first solid state that helped to usher in digital revolution. For any new semiconductor, therefore, fabrication and characterization BJT are important for both technological importance historical significance. Here, we demonstrate a device exfoliated TMD WSe2. We use buried gates electrostatically create doped regions with back-to-back p–n junctions. two central characteristics...

In this paper, we introduce a novel reconfigurable graphene logic based on p-n junctions. device, switching is accomplished by using co-planar split gates that modulate the properties are unique to graphene, including ambipolar conduction, electrostatic doping, and angular dependent carrier reflection. addition, use of these control can dynamically change operation leading multi-functional logic. A device model derived from transmission probability across junction for allowing quantitative...

Using various size rectangular mesas formed by photolithographically patterning and etching on single-crystal Bi2Sr2Ca1Cu2Ox superconductors, we have obtained c-axis volt-ampere characteristics as a function of magnetic field applied parallel to the a-b planes. Enhanced sensitivity with perpendicular long side was observed even in dimensions smaller than penetration depth λc. This can be explained terms viscous flow Josephson vortices. The measurements are good quantitative agreement...

The authors show that a carbon nanotube p-n diode is very sensitive probe of optical transitions in individual single-walled nanotubes. In the photocurrent spectra, an alternating sequence resonant peaks from dissociation excitons and exciton-phonon bound states, for lowest higher electronic subbands, observed. At intermediate energy, onset continuum observed allows measurement exciton binding energies. Both energy follow inverse diameter relation as expected general theory

Comparing photoconductivity measurements, using p-n diodes formed along individual single-walled carbon nanotubes (SWNT), with modeling results, allows determination of the quantum efficiency, optical capture cross section, and oscillator strength first (E11) second (E22) excitonic transitions SWNTs. This is in infrared region spectrum, where little experimental work on SWNT absorption has been reported to date. We estimate efficiency (η) ~1-5% provide a correlation η, for E11 E22 nanotube...

We experimentally investigate charge carrier transport in a graphene $p\ensuremath{-}n$ junction device by using independent $p$-type and $n$-type electrostatic gating which allow full characterization of the interface quantum Hall regime covering wide range filling factors $[\ensuremath{-}10\ensuremath{\le}({\ensuremath{\nu}}_{1},\phantom{\rule{0.16em}{0ex}}{\ensuremath{\nu}}_{2})\ensuremath{\le}10]$. Recent measurements across this quantized presume that equilibration all...

Scattering processes in quantum materials emerge as resonances electronic transport, including confined modes, Andreev states, and Yu-Shiba-Rusinov states. However, most instances, these are driven by a single scattering mechanism. Here, we show the appearance of due to combination two simultaneous mechanisms, one from superconductivity other graphene p-n junctions. These stem reflection Klein tunneling that occur at different interfaces hole-doped region formed boundary with superconducting...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Zhaoying Hu, Dhiraj Prasad Sinha, Ji Ung Lee, Michael Liehr; Substrate dielectric effects on graphene field effect transistors. J. Appl. Phys. 21 May 2014; 115 (19): 194507. https://doi.org/10.1063/1.4879236 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks...

The measurement of the electronic bandgap and exciton binding energy in quasi-one-dimensional materials such as carbon nanotubes is challenging due to many-body effects strong electron-electron interactions. Unlike bulk semiconductors, where well known, optical resonance low-dimensional semiconductors dominated by excitons, making their more difficult measure. In this work, we measure networks polymer-wrapped semiconducting single-walled (s-SWCNTs) using non-ideal

The band gap of a semiconductor is one its most fundamental properties. It the defining parameters for applications, including nanoelectronic and nanophotonic devices. Measuring gap, however, has received little attention quasi-one-dimensional materials, single-walled carbon nanotubes. Here we show that current-voltage characteristics p-n diodes fabricated with semiconducting nanotubes can be used along excitonic transitions to measure both (intrinsic) renormalized nanotube band-gaps.

We present simulations of quantum transport in graphene p-n junctions $(pn\mathrm{Js})$ which moir\'e superlattice potentials are incorporated to demonstrate the interplay between $pn\mathrm{Js}$ and potentials. It is shown that longitudinal Hall resistivity maps can be strongly modulated by $pn\mathrm{J}$ profile, junction height, Device resistance measurements subsequently performed on graphene/hexagonal-boron-nitride heterostructure samples with accurate alignment crystallographic...

We demonstrate the use of a quantum transport model to study heavily graded graphene $p\text{\ensuremath{-}}n$ junctions in Hall regime. A combination interface roughness and delta function disorder potential allows us compare experimental results on different devices from literature. find that wide suppress mixing $n\ensuremath{\ne}0$ Landau levels. Our simulations spatially resolve carrier device, revealing separation higher order levels strongly junctions, which suppresses mixing.

We measured the total ionizing dose response of gate-all-around silicon nanowire n- and pMOSFETs to x-ray doses up 2Mrad(SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ). show that they are radiation hard, with no degradation in threshold voltage, off-state current, or subthreshold slope, even at highest for a wide range bias conditions. attribute this intrinsically rad-hard feature device design, where channel is longer contact any...

Abstract We show that by adding only two fitting parameters to a purely ballistic transport model, we can accurately characterize the current-voltage characteristics of nanoscale MOSFETs. The model is an extension Natori’s and includes transmission probability drain-channel coupling parameter. latter parameter gives rise theoretical R ON significantly larger than those predicted previously. To validate our fabricated n-channel MOSFETs with varying channel lengths. length dependence these...

While a number of studies have reported evidence localized states in carbon nanotube devices, the density distribution these has not been until now. By measuring trap emission current field-effect transistors, we observe prominent exponential tail near band edge. Since continuous distributions are typically associated with highly disordered systems, this observation was quite unexpected nanotubes, which nearly ideal crystals. This continuum may explain variety phenomena including universal...

We show that carbon nanotubes are robust under high H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> <sup xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> ion fluences. draw this conclusion by analyzing radiation-induced defects in reconfigurable single-walled nanotube p-n diodes with partially suspended nanotubes. Our analysis any created through radiation is likely the result of interactions between and substrate, whereas region...