13 research outputs found
Dielectrophoretic Growth of Platinum Nanowires: Concentration and Temperature Dependence of the Growth Velocity
Effect of Waveform of ac Voltage on the Morphology and Crystallinity of Electrochemically Assembled Platinum Nanowires
Quantitative Analysis of Gold Nanorod Alignment after Electric Field-Assisted Deposition
Conductance Control in VO2 Nanowires by Surface Doping with Gold Nanoparticles
The material properties of semiconductor nanowires are greatly affected by electrical, optical, and chemical processes occurring at their surfaces because of the very large surface-to-volume ratio. Precise control over doping as well as the surface charge properties has been demonstrated in thin films and nanowires for fundamental physics and application-oriented research. However, surface doping behavior is expected to differ markedly from bulk doping in conventional semiconductor materials. Here, we show that placing gold nanoparticles, in controlled manner, on the surface of an insulating vanadium dioxide nanowire introduces local charge carriers in the nanowire, and one could, in principle, completely and continuously alter the material properties of the nanowire and obtain any intermediate level of conductivity. The current in the nanowire increased by nearly 3 times when gold nanoparticles of 10(11) cm(-2) order of density were controllably placed on the nanowire surface. A strong quadratic space-charge limited (SCL) transport behavior was also observed from the conductance curve suggesting the formation of two-dimensional (2D) electron-gas-like confined layer in the nanowire with adsorbed Au NPs. In addition to stimulating scientific interest, such unusual surface doping phenomena may lead to new applications of vanadium dioxide-based electronic, optical, and chemical sensing nanodevices.close
Atomistic simulation of agglomeration of metal nanoparticles considering the induced charge density of surface atoms
Spontaneous Self-Organization Enables Dielectrophoresis of Small Nanoparticles and Formation of Photoconductive Microbridges
A Device for Performing Lateral Conductance Measurements on Individual Double-Stranded DNA Molecules
A nanofluidic device is described that is capable of electrically monitoring the driven translocation of DNA molecules through a nanochannel. This is achieved by intersecting a long transport channel with a shorter orthogonal nanochannel. The ionic conductance of this transverse nanochannel is monitored while DNA is electrokinetically driven through the transport channel. When DNA passes the intersection, the transverse conductance is altered, resulting in a transient current response. In 1 M KCl solutions, this was found to be a current enhancement of 5–25%, relative to the baseline transverse ionic current. Two different device geometries were investigated. In one device, the DNA was detected after it was fully inserted into and translocating through the transport nanochannel. In the other device, the DNA was detected while it was in the process of entering the nanochannel. It was found that these two conditions are characterized by different transport dynamics. Simultaneous optical and electrical monitoring of DNA translocation confirmed that the transient events originated from DNA transport through the nanochannel intersection