Related papers: Strain and doping transfer between suspended and s…
Raman spectroscopy is a powerful tool for characterizing the local properties of graphene. Here, we introduce a method for evaluating unknown strain configurations and simultaneous doping. It relies on separating the effects of hydrostatic…
The pressure evolution of the Raman spectrum of graphene grown by chemical vapour deposition on polycrystalline copper is investigated with the use of a polar and a non-polar pressure transmitting medium (PTM). The G and 2D Raman bands…
Graphene, due to its superior stretchability, exhibits rich structural deformation behaviors and its strain-engineering has proven useful in modifying its electronic and magnetic properties. Despite the strain-sensitivity of the Raman G and…
We use confocal Raman microscopy and modified vector analysis methods to investigate the nanoscale origin of strain and carrier concentration in exfoliated graphene-hexagonal boron nitride (hBN) heterostructures on silicon dioxide (SiO2).…
Accurate and simple local strain assessment in graphene is one of the crucial tasks in device characterization. Raman spectroscopy is often used for that purpose through monitoring of the G and 2D modes. However, the shifts of those two…
The recent emergence of strain gradient engineering directly affects the nanomechanics, optoelectronics and thermal transport fields in 2D materials. More specifically, large suspended graphene under very high stress represents the…
In this letter we use graphene bubbles to study the Raman spectrum of graphene under biaxial (e.g. isotropic) strain. Our Gruneisen parameters are in excellent agreement with the theoretical values. Discrepancy in the previously reported…
Strain, both naturally occurring and deliberately engineered, can have a considerable effect on the structural and electronic properties of 2D and layered materials. Uniaxial or biaxial heterostrain modifies the stacking arrangement of…
Since lattice strain and charge density affect various material properties of graphene, a reliable and efficient method is required for quantification of the two variables. While Raman spectroscopy is sensitive and non-destructive, its…
Mechanical properties of graphene prepared by chemical vapor deposition (CVD) are not easily comparable to the properties of nearly perfect graphene prepared by mechanical cleavage. In this work, we attempt to investigate the mechanical…
Avoiding charge density variations and impurities in graphene is vital for high-quality graphene-based devices. Here, we demonstrate an optical method using Raman 2D peak-split to monitor charge density variations in the range 1-25e10 cm-2.…
Controlled modulation of electronic band structure in two-dimensional (2D) materials via doping is crucial for devices fabrication. For instance doped graphene has been envisaged for various applications like sensors, super-capacitors,…
Two-dimensional (2D) materials such as graphene offer a variety of outstanding properties for a wide range of applications. Their transport properties in particular present a rich field of study. However, the studies of transport properties…
The Raman shift, broadening, and relative Raman intensities of bilayer graphene are computed as functions of the electron concentration. We include dynamic effects for the phonon frequencies and we consider the gap induced in the band…
We demonstrated doping in 2D monolayer graphene via local electrical stressing. The doping, confirmed by the resistance-voltage transfer characteristics of the graphene system, is observed to continuously tunable from N-type to P-type as…
Graphene is a mechanically robust 2D material promising for flexible optoelectronic applications. However, its electromagnetic properties under strain are experimentally poorly understood. Here we present the far-infrared transmission…
Tuning the charge carrier density of two-dimensional (2D) materials by incorporating dopants into the crystal lattice is a challenging task. An attractive alternative is the surface transfer doping by adsorption of molecules on 2D crystals,…
We present spatially resolved Raman images of the G and 2D lines of single-layer graphene flakes. The spatial fluctuations of G and 2D lines are correlated and are thus shown to be affiliated with local doping domains. We investigate the…
Among the different strategies used to induce the opening of a band gap in graphene, one common practice is through chemical doping. While a gap may me opened in this way, disorder-induced scattering is an unwanted side-effect that impacts…
Electrostatic gating offers elegant ways to simultaneously strain and dope atomically thin membranes. Here, we report on a detailed \textit{in situ} Raman scattering study on graphene, suspended over a Si/SiO$_2$ substrate. In such a…