APL Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

26 Nov 2012

Volume 101, Issue 22, Articles (22xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 101, 221101 (2012); http://dx.doi.org/10.1063/1.4767646 (5 pages)

Mikhail A. Kats, Deepika Sharma, Jiao Lin, Patrice Genevet, Romain Blanchard, Zheng Yang, M. Mumtaz Qazilbash, D. N. Basov, Shriram Ramanathan, and Federico Capasso
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Reactive oxygen species controllable non-thermal helium plasmas for evaluation of plasmid DNA strand breaks

Jae Young Kim, Dong-Hoon Lee, John Ballato, Weiguo Cao, and Sung-O Kim

Appl. Phys. Lett. 101, 224101 (2012); http://dx.doi.org/10.1063/1.4768922 (5 pages)

Online Publication Date: 26 November 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Non-thermal, oxygen-rich helium plasmas were investigated to achieve an enhanced reactive oxygen species concentration at low voltage driving conditions. A non-thermal plasma device was fabricated based on a theta-shaped tube, and its potential was investigated for use in topological alteration of plasmid DNA. The optical emission spectra of the plasma showed that the oxygen flow affected the plasma properties, even though an oxygen plasma was not produced. The plasmid DNA strand breaks became more significant with the addition of oxygen flow to the helium in a single hollow, theta-shaped tube with other experimental conditions being unchanged.
Show PACS
87.80.-y Biophysical techniques (research methods)
87.14.gk DNA
87.15.K- Molecular interactions; membrane-protein interactions
52.25.Os Emission, absorption, and scattering of electromagnetic radiation
52.77.-j Plasma applications

Plasma flares in high power impulse magnetron sputtering

Pavel A. Ni, Christian Hornschuch, Matjaž Panjan, and André Anders

Appl. Phys. Lett. 101, 224102 (2012); http://dx.doi.org/10.1063/1.4768925 (5 pages)

Online Publication Date: 26 November 2012

Full Text: Read Online (HTML) | Download PDF

multimedia

Show Abstract
Self-organized ionization zones and associated plasma flares were recorded with fast cameras in side-on view. Flare velocities were estimated to be about 20 000 m/s suggesting that the local tangential field Eξ is about 2000 V/m based on a concept where flare-causing electrons are initially ejected by Eξ×B drift. At distances of 10 mm and greater from the target, where the electric field is very small, plasma flares are guided by the magnetic field B.
Show PACS
52.25.Fi Transport properties
52.25.Jm Ionization of plasmas
52.70.Kz Optical (ultraviolet, visible, infrared) measurements
52.80.-s Electric discharges

Pulsed laser ablation plasmas generated in CO2 under high-pressure conditions up to supercritical fluid

Toru Kato, Sven Stauss, Satoshi Kato, Keiichiro Urabe, Motoyoshi Baba, Tohru Suemoto, and Kazuo Terashima

Appl. Phys. Lett. 101, 224103 (2012); http://dx.doi.org/10.1063/1.4767839 (5 pages)

Online Publication Date: 27 November 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Pulsed laser ablation of solids in supercritical media has a large potential for nanomaterials fabrication. We investigated plasmas generated by pulsed laser ablation of Ni targets in CO2 at pressures ranging from 0.1 to 16 MPa at 304.5 K. Plasma species were characterized by optical emission spectroscopy, and the evolution of cavitation bubbles and shockwaves were observed by time-resolved shadowgraph imaging. Ni and O atomic emissions decreased with increasing gas pressure; however, near the critical point the intensities reached local maxima, probably due to the enhancement of the plasma excitation and effective quenching resulting from the large density fluctuation.
Show PACS
52.25.Os Emission, absorption, and scattering of electromagnetic radiation
52.35.Tc Shock waves and discontinuities
52.38.Mf Laser ablation
52.50.Jm Plasma production and heating by laser beams (laser-foil, laser-cluster, etc.)
52.70.Kz Optical (ultraviolet, visible, infrared) measurements
52.25.Gj Fluctuation and chaos phenomena

Low cost ion implantation technique

M. C. Salvadori, F. S. Teixeira, L. G. Sgubin, W. W. R. Araujo, R. E. Spirin, E. M. Oks, K. M. Yu, and I. G. Brown

Appl. Phys. Lett. 101, 224104 (2012); http://dx.doi.org/10.1063/1.4768699 (4 pages)

Online Publication Date: 27 November 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We describe an approach to ion implantation in which the plasma and its electronics are held at ground potential and the ion beam is formed and injected energetically into a space held at high negative potential. The technique allows considerable savings both economically and technologically, rendering feasible ion implantation applications that might otherwise not be possible for many researchers and laboratories. Here, we describe the device and the results of tests demonstrating Nb implantation at 90 keV ion energy and dose about 2 × 1016 cm−2.
Show PACS
61.72.up Other materials

Experimental verification of field rotating with invisibility by full tensor transmission-line metamaterials

Guochang Liu, Chao Li, Chao Chen, Zheng Lu, and Guangyou Fang

Appl. Phys. Lett. 101, 224105 (2012); http://dx.doi.org/10.1063/1.4768003 (4 pages)

Online Publication Date: 27 November 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We demonstrate the experimental realization of a field rotator based on transmission line (TL) networks. The anisotropic and non-diagonal medium parameters of the field rotator are controlled by the coupling between the different branches of tensor TL metamaterials. Taking advantages of full parameters realization, the effect of field rotating companied with invisibility is verified. The non-resonant property of the TL structure also leads to a relatively broad bandwidth of the field rotation function, which is quantitatively evaluated based on our experimental results.
Show PACS
42.70.-a Optical materials
02.10.Ud Linear algebra

Quasi-equilibrium electron density along a magnetic field line

Hann-Shin Mao and Richard Wirz

Appl. Phys. Lett. 101, 224106 (2012); http://dx.doi.org/10.1063/1.4768301 (4 pages)

Online Publication Date: 27 November 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A methodology is developed to determine the density of high-energy electrons along a magnetic field line for a low-β plasma. This method avoids the expense and statistical noise of traditional particle tracking techniques commonly used for high-energy electrons in bombardment plasma generators. By preserving the magnetic mirror and assuming a mixing timescale, typically the elastic collision frequency with neutrals, a quasi-equilibrium electron distribution can be calculated. Following the transient decay, the analysis shows that both the normalized density and the reduction fraction due to collision converge to a single quasi-equilibrium solution.
Show PACS
52.25.Fi Transport properties
28.52.Av Theory, design, and computerized simulation
52.55.-s Magnetic confinement and equilibrium
52.75.-d Plasma devices
52.20.Fs Electron collisions

Divertor conditions relevant for fusion reactors achieved with linear plasma generator

H. J. N. van Eck, A. W. Kleyn, A. Lof, H. J. van der Meiden, G. J. van Rooij, J. Scholten, and P. A. Zeijlmans van Emmichoven

Appl. Phys. Lett. 101, 224107 (2012); http://dx.doi.org/10.1063/1.4768302 (4 pages)

Online Publication Date: 27 November 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Intense magnetized hydrogen and deuterium plasmas have been produced with electron densities up to 3.6 × 1020 m−3 and electron temperatures up to 3.7 eV with a linear plasma generator. Exposure of a W target has led to average heat and particle flux densities well in excess of 4 MW m−2 and 1024 m−2 s−1, respectively. We have shown that the plasma surface interactions are dominated by the incoming ions. The achieved conditions correspond very well to the projected conditions at the divertor strike zones of fusion reactors such as ITER. In addition, the machine has an unprecedented high gas efficiency.
Show PACS
52.55.Fa Tokamaks, spherical tokamaks
52.40.Hf Plasma-material interactions; boundary layer effects
52.25.Xz Magnetized plasmas

A fast-converging iterative method for X-ray in-line phase contrast tomography

Nghia T. Vo, Robert C. Atwood, Herbert O. Moser, Peter D. Lee, Mark B. H. Breese, and Michael Drakopoulos

Appl. Phys. Lett. 101, 224108 (2012); http://dx.doi.org/10.1063/1.4769046 (4 pages)

Online Publication Date: 28 November 2012

Full Text: Read Online (HTML) | Download PDF

multimedia

Show Abstract
X-ray in-line phase contrast tomography holds great promise for the quantitative analysis of soft materials. However, its applications have been limited, so far, by the fact that direct methods based on the transport-of-intensity equation and the contrast transfer function are sensitive to noise and applicable only to limited types of samples. Here, we propose an iterative method based on the Gerchberg-Saxton algorithm (R. W. Gerchberg and W. O. Saxton, Optik 35, 237 (1972)), but overcoming its slow convergence by an acceleration technique, named random signed feedback, which shows an excellent performance, both in numerical simulation and tomographic experiment, of discriminating various polymers even when using 53 keV synchrotron X-rays.
Show PACS
07.85.-m X- and γ-ray instruments
02.60.-x Numerical approximation and analysis
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close