100 citations · 210 across the 19 of their papers we have counts for
19 papers
Streamlined Inexpensive Integration of a Growth Facility and Scanning Tunneling Microscope for in situ Characterization
P. Xu, D. Qi, S. D. Barber +3
The integration of a scanning tunneling microscope chamber with a sample growth facility using non-custom, commercially available parts is described. The facility also features a n…
Controlling Mn Depth Profiles in GaMnAs During High-Temperature Molecular Beam Epitaxial Growth
P. Xu, D. Qi, M. L. Ackerman +2
Mn-doped GaAs thin films were grown at a high substrate temperature of 580 C. During the growth process, the Mn cell temperature was ramped at different rates, resulting in a varie…
Giant Surface Charge Density of Graphene Resolved From Scanning Tunneling Microscopy and First-Principles Theory
P. Xu, Y. Yang, S. D. Barber +6
In this work, systematic constant-bias, variable-current scanning tunneling microscopy (STM) measurements and STM simulations from density-functional theory are made, yielding crit…
Atomic Control of Strain in Freestanding Graphene
P. Xu, Y. Yang, S. D. Barber +8
In this study, we describe a new experimental approach based on constant-current scanning tunneling spectroscopy to controllably and reversibly pull freestanding graphene membranes…
High-Percentage Success Method for Preparing and Pre-Evaluating Tungsten Tips for Atomic-Resolution Scanning Tunneling Microscopy
J. K. Schoelz, P. Xu, S. D. Barber +5
A custom double-lamella method is presented for electrochemically etching tungsten wire for use as tips in scanning tunneling microscopy (STM). For comparison, tips were also manuf…
A Pathway between Bernal and Rhombohedral Stacked Graphene Layers with Scanning Tunneling Microscopy
P. Xu, Y. Yang, D. Qi +7
Horizontal shifts in the top layer of highly oriented pyrolytic graphite, induced by a scanning tunneling microscope (STM) tip, are presented. Excellent agreement is found between…
Schottky barrier and attenuation length for hot hole injection in non-epitaxial Au on p-type GaAs
I. Sitnitsky, J. J. Garramone, J. R. Abel +6
Ballistic electron emission microscopy (BEEM) was performed to obtain nanoscale current versus bias characteristics of non-epitaxial Au on p-type GaAs in order to accurately measur…
Electromechanical properties of freestanding graphene functionalized with tin oxide (SnO2) nanoparticles
L. Dong, J. Hansen, P. Xu +5
Freestanding graphene membranes were functionalized with SnO2 nanoparticles. A detailed procedure providing uniform coverage and chemical synthesis is presented. Elemental composit…
Electronic transition from graphite to graphene via controlled movement of the top layer with scanning tunneling microscopy
P. Xu, Y. Yang, D. Qi +5
A series of measurements using a technique called electrostatic-manipulation scanning tunneling microscopy (EM-STM) were performed on a highly-oriented pyrolytic graphite surface.…
New Scanning Tunneling Microscopy Technique Enables Systematic Study of the Unique Electronic Transition from Graphite to Graphene
P. Xu, Y. Yang, S. D. Barber +5
A series of measurements using a novel technique called electrostatic-manipulation scanning tunneling microscopy were performed on a highly-oriented pyrolytic graphite (HOPG) surfa…
Broad frequency and amplitude control of vibration in freestanding graphene via scanning tunneling microscopy with calculated dynamic pseudo-magnetic fields
P. Xu, J. K. Schoelz, S. D. Barber +2
A technique to locally generate mechanical vibrations in freestanding graphene using scanning tunneling microscopy (STM) is presented. The frequency of the mechanical vibrations is…
Graphene Manipulation on 4H-SiC(0001) Using Scanning Tunneling Microscopy
P. Xu, M. L. Ackerman, S. D. Barber +8
Atomic-scale topography of epitaxial multilayer graphene grown on 4H-SiC(0001) was investigated using scanning tunneling microscopy (STM). Bunched nano-ridges ten times smaller tha…
Atomic-Scale Movement Induced in Nano-Ridges by Scanning Tunneling Microscopy on Epitaxial Graphene Grown on 4H-SiC(0001)
P. Xu, S. D. Barber, J. K. Schoelz +8
Nanoscale ridges in epitaxial multilayer graphene grown on the silicon face of 4 degree off-cut 4H-SiC (0001) were found using scanning tunneling microscopy (STM). These nano-ridge…
Role of bias voltage and tunneling current in the perpendicular displacements of freestanding graphene via scanning tunneling microscopy
P. Xu, S. D. Barber, M. L. Ackerman +2
Systematic displacement measurements of freestanding graphene as a function of applied bias voltage and tunneling current setpoint using scanning tunneling microscopy (STM) are pre…
Etch-stop method for reliably fabricating sharp yet mechanically stable scanning tunneling microscope tips
G. Basnet, J. K. Schoelz, P. Xu +3
An extension of the direct-current, double-lamella drop-off technique for electrochemically etching tungsten scanning-tunneling-microscope tips is presented. The key fabrication st…
Competing scanning tunneling microscope tip-interlayer interactions for twisted multilayer graphene on the a-plane SiC surface
P. Xu, M. L. Ackerman, S. D. Barber +7
Scanning tunneling microscopy (STM) images are obtained for the first time on few layer and twisted multilayer epitaxial graphene states synthesized on n+ 6H-SiC a-plane non-polar…
Thermal mirror buckling in freestanding graphene locally controlled by scanning tunneling microscopy
M. Neek-Amal, P. Xu, J. K. Schoelz +5
Knowledge of and control over the curvature of ripples in freestanding graphene are desirable for fabricating and designing flexible electronic devices, and recent progress in thes…
Unusual ultralow frequency fluctuations in freestanding graphene
P. Xu, M. Neek-Amal, S. D. Barber +5
Intrinsic ripples in freestanding graphene have been exceedingly difficult to study. Individual ripple geometry was recently imaged using scanning tunneling microscopy, but these m…
Self-Organized Platinum Nanoparticles on Freestanding Graphene
Peng Xu, Lifeng Dong, Mehdi Neek-Amal +8
Freestanding graphene membranes were successfully functionalized with platinum nanoparticles (Pt NPs). High-resolution transmission electron microscopy revealed a homogeneous distr…