In-situ electrochemical fabrication of natural contacts on single nanowires

We report a template-based in-situ electrochemical method for fabricating natural electric contacts on single nanowires using a pair of cross-patterned electrodes. Such electric contacts are highly stable upon thermal cycling between room temperature and milli-Kelvin temperatures. Direct imaging of the single-nanowire contacts using scanning electron microscopy is also demonstrated.Comment: 13 pages, 4 figure

First-Principles Study on Leakage Current through Si/SiO2_2 Interface

The relationship between the presence of defects at the stacking structure of the Si/SiO$_2$ interface and leakage current is theoretically studied by first-principles calculation. I found that the leakage current through the interface with dangling bonds is 530 times larger than that without any defects, which is expected to lead to dielectric breakdown. The direction of the dangling bonds is closely related to the performance of the oxide as an insulator. In addition, it is proved that the termination of the dangling bonds by hydrogen atoms is effective for reducing the leakage current.Comment: 11 pages. to be published in Phys. Rev.

The City: Art and the Urban Environment

The City: Art and the Urban Environment is the fifth annual exhibition curated by students enrolled in the Art History Methods class. This exhibition draws on the students’ newly developed expertise in art-historical methodologies and provides an opportunity for sustained research and an engaged curatorial experience. Working with a selection of paintings, prints, and photographs, students Angelique Acevedo ’19, Sidney Caccioppoli ’21, Abigail Coakley ’20, Chris Condon ’18, Alyssa DiMaria ’19, Carolyn Hauk ’21, Lucas Kiesel ’20, Noa Leibson ’20, Erin O’Brien ’19, Elise Quick ’21, Sara Rinehart ’19, and Emily Roush ’21 carefully consider depictions of the urban environment in relation to significant social, economic, artistic, and aesthetic developments. [excerpt]https://cupola.gettysburg.edu/artcatalogs/1029/thumbnail.jp

Shape Transition of Nanostructures created on Si(100) surfaces after MeV Implantation

We have studied the modification in the Surface morphology of the Si(100) surfaces after 1.5 MeV Sb implantation. Scanning Probe Microscopy has been utilized to investigate the ion implanted surfaces. We observe the formation of nano-sized defect features on the Si surfaces for various fluences. These nanostructures are elliptical in shape and inflate in sizefor higher fluences. Furthermore, these nanostructures undergo a shape transition from an elliptical shape to a circular-like at a high fluence. We will also discuss the modification in surface roughness as a function of Sb fluence.Comment: 9 pages, 4 figure

Electrical conduction of silicon oxide containing silicon quantum dots

Current-voltage measurements have been made at room temperature on a Si-rich silicon oxide film deposited via Electron-Cyclotron Resonance Plasma Enhanced Chemical Vapor Deposition (ECR-PECVD) and annealed at 750 - 1000$^\circ$C. The thickness of oxide between Si quantum dots embedded in the film increases with the increase of annealing temperature. This leads to the decrease of current density as the annealing temperature is increased. Assuming the Fowler-Nordheim tunneling mechanism in large electric fields, we obtain an effective barrier height $\phi_{eff}$ of $\sim$ 0.7 $\pm$ 0.1 eV for an electron tunnelling through an oxide layer between Si quantum dots. The Frenkel-Poole effect can also be used to adequately explain the electrical conduction of the film under the influence of large electric fields. We suggest that at room temperature Si quantum dots can be regarded as traps that capture and emit electrons by means of tunneling.Comment: 14 pages, 5 figures, submitted to J. Phys. Conden. Mat

Starships and Enterprise: Private Spaceflight Companies\u27 Property Rights and the U.S. Commercial Space Launch Competitiveness Act

(Excerpt) This Note utilizes SLCA as a focal point to discuss the potential of domestic regulation that grants private companies property rights in harvested outer space resources and how, if at all, these rights can exist within the boundaries of current international obligations. First, it outlines current international obligations in space law, delving into the treaties governing space law and analagous obligations in Antarctica and the deep sea. Second, this Note discusses how SLCA meets those guidelines and where it falls short. This Part draws on the Roman law principles of res nullius and res communis, the supporting sections of the Act itself, and analogies to the water law regime in the western United States to both support the Act and establish its shortcomings. Finally, this Note concludes that private companies can harvest space resources under SLCA consistently with the United States’ international obligations, but a sunset provision on this property rights regime, limiting its duration to a set term of years or until an updated international treaty regime is established, may be necessary to remain in compliance with international obligations

Starships and Enterprise: Private Spaceflight Companies\u27 Property Rights and the U.S. Commercial Space Launch Competitiveness Act

(Excerpt) This Note utilizes SLCA as a focal point to discuss the potential of domestic regulation that grants private companies property rights in harvested outer space resources and how, if at all, these rights can exist within the boundaries of current international obligations. First, it outlines current international obligations in space law, delving into the treaties governing space law and analagous obligations in Antarctica and the deep sea. Second, this Note discusses how SLCA meets those guidelines and where it falls short. This Part draws on the Roman law principles of res nullius and res communis, the supporting sections of the Act itself, and analogies to the water law regime in the western United States to both support the Act and establish its shortcomings. Finally, this Note concludes that private companies can harvest space resources under SLCA consistently with the United States’ international obligations, but a sunset provision on this property rights regime, limiting its duration to a set term of years or until an updated international treaty regime is established, may be necessary to remain in compliance with international obligations