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

10 Mar 2003

Volume 82, Issue 10, pp. 1497-1639

Issue Cover Spotlight Figure

Appl. Phys. Lett. 82, 1610 (2003); http://dx.doi.org/10.1063/1.1559439 (3 pages)

Yong Chen, Douglas A. A. Ohlberg, Xuema Li, Duncan R. Stewart, R. Stanley Williams, Jan O. Jeppesen, Kent A. Nielsen, J. Fraser Stoddart, Deirdre L. Olynick, and Erik Anderson
Enlarge Image | Read More
Page 2 of 2 Pages Previous Page | Jump to Page
back to top
RSS Feeds

Fabrication of spin-frustrated Sm2Mo2O7 epitaxial films: High throughput optimization using a temperature gradient method

J. Nishimura, T. Fukumura, M. Ohtani, Y. Taguchi, M. Kawasaki, I. Ohkubo, H. Koinuma, H. Ohguchi, K. Ono, M. Oshima, and Y. Tokura

Appl. Phys. Lett. 82, 1571 (2003); http://dx.doi.org/10.1063/1.1559440 (3 pages) | Cited 5 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Epitaxial thin films of pyrochlore-type ferromagnetic molybdates Sm2Mo2O7, as a geometrically spin-frustrated system, were fabricated by a pulsed-laser deposition. The temperature gradient method combined with the concurrent x-ray diffraction method was exploited for high throughput optimization of the film quality. The excess supply of Mo for compensating the volatile Mo-related species improved the crystallinity. The resistivity and magnetization of the optimized film were 3 mΩ cm and 0.8 μB/Mo at 10 K, respectively, being similar to those of a single crystal. The observed finite anomalous Hall term that persists down to the lowest temperature reflects an appearance of spin chirality in this spin-frustrated system. © 2003 American Institute of Physics.
Show PACS
81.15.Fg Pulsed laser ablation deposition
68.55.A- Nucleation and growth
75.70.Ak Magnetic properties of monolayers and thin films
75.50.Dd Nonmetallic ferromagnetic materials
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
72.20.My Galvanomagnetic and other magnetotransport effects
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
73.61.Ng Insulators
72.80.Sk Insulators

Exchange-spring permanent magnet particles produced by spark-erosion

M. F. Hansen, K. S. Vecchio, F. T. Parker, F. E. Spada, and A. E. Berkowitz

Appl. Phys. Lett. 82, 1574 (2003); http://dx.doi.org/10.1063/1.1560559 (3 pages) | Cited 7 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Exchange-spring permanent magnet particles of composition Pr6.93Fe85.7B5.95Nb1.39 in at. % were prepared by spark-erosion in liquid argon. The best exchange-spring properties were achieved after vacuum annealing the as-sparked powders at 700 °C for ∼5 min, and did not change significantly for anneals up to 120 min. This behavior suggests that the equilibrium dimensions of the “hard” and “soft” phases were determined by the sizes of the spark-eroded particles in which they developed. The Pr2Fe14B phase developed as spheres, likely single crystals, in an α-Fe+Fe2B matrix. © 2003 American Institute of Physics.
Show PACS
07.55.Db Generation of magnetic fields; magnets
75.50.Ww Permanent magnets
75.50.Tt Fine-particle systems; nanocrystalline materials
75.30.Et Exchange and superexchange interactions
81.40.Gh Other heat and thermomechanical treatments
81.05.Bx Metals, semimetals, and alloys
81.20.Ev Powder processing: powder metallurgy, compaction, sintering, mechanical alloying, and granulation
back to top
RSS Feeds

Recovery process of degraded ferroelectric properties in the forming-gas-annealed Pt/Bi4−xLaxTi3O12/Pt capacitor

Uong Chon and Hyun M. Jang

Appl. Phys. Lett. 82, 1577 (2003); http://dx.doi.org/10.1063/1.1558970 (3 pages) | Cited 4 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The recovery of ferroelectric properties in the forming-gas-annealed Pt/Bi4−xLaxTi3O12/Pt (Pt/BLT/Pt) capacitor was studied by examining changes in ferroelectric responses, phase evolution, and spatial distributions of relevant species during the recovery annealing. The degraded ferroelectric properties were practically restored to their original values after the recovery annealing at 600 °C for 10 min in an O2 atmosphere. The following recovery process has been delineated from the present study: (i) the removal of impregnated protons from the degraded capacitor due to the chemical potential difference of protons between the forming-gas-annealed capacitor and the contacting atmosphere, and (ii) the restoration of perovskite BLT phase with the help of replenishment of the Bi and oxygen losses via diffusion from the neighboring intact region to the Bi-depleted columnar region located beneath the top Pt electrode. © 2003 American Institute of Physics.
Show PACS
85.50.-n Dielectric, ferroelectric, and piezoelectric devices
84.32.Tt Capacitors
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
81.40.Gh Other heat and thermomechanical treatments
66.30.H- Self-diffusion and ionic conduction in nonmetals
77.80.Dj Domain structure; hysteresis
77.22.Ej Polarization and depolarization

Selective desorption of interfacial SiO2

M. Copel

Appl. Phys. Lett. 82, 1580 (2003); http://dx.doi.org/10.1063/1.1559647 (3 pages) | Cited 17 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, we report the selective thermal decomposition of SiO2 from a silicate/Si(001) interface, without silicidation of the dielectric. We observe kinetics that are similar to SiO2 desorption from Si(001), which takes place by SiO volatilization, suggesting that a similar mechanism is responsible at a buried interface. Interface desorption is a route to direct dielectric/silicon structures without prior removal of SiO2. © 2003 American Institute of Physics.
Show PACS
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces
68.43.Vx Thermal desorption

Delayed fracture of lead zirconate titanate ferroelectric ceramics under sustained electric field

Y. Wang, W. Y. Chu, K. W. Gao, Y. J. Su, and L. J. Qiao

Appl. Phys. Lett. 82, 1583 (2003); http://dx.doi.org/10.1063/1.1558958 (3 pages) | Cited 10 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, we report on delayed fracture of lead zirconate titanate ceramics with a Zr/Ti ratio of 52/48(PZT-5) ferroelectric ceramics in silicon oil under sustained electric field, and that in silicon oil or moist atmosphere under sustained mechanical load. The experimental results show that sustained electric fields may cause delayed fracture of PZT-5 ceramics and there is a threshold field for the delayed fracture. The threshold electric field is less than one third of the critical electric field to cause instant fracture and is also half of the coercive field of the PZT-5 ceramics. © 2003 American Institute of Physics.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.65.-j Piezoelectricity and electromechanical effects
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
62.20.M- Structural failure of materials

Theory of polarization enhancement in epitaxial BaTiO3/SrTiO3 superlattices

J. B. Neaton and K. M. Rabe

Appl. Phys. Lett. 82, 1586 (2003); http://dx.doi.org/10.1063/1.1559651 (3 pages) | Cited 27 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The spontaneous polarization of epitaxial BaTiO3/SrTiO3 superlattices is studied as a function of composition using first-principles density-functional theory within the local density approximation. With the in-plane lattice parameter fixed to that of bulk SrTiO3, the computed superlattice polarization is enhanced above that of bulk BaTiO3 for superlattices with BaTiO3 fraction larger than 40%. In contrast to their bulk paraelectric character, the SrTiO3 layers are found to be tetragonal and polar, possessing nearly the same polarization as the BaTiO3 layers. General electrostatic arguments elucidate the origin of the polarization in the SrTiO3 layers, with important implications for other nanostructured ferroelectrics. © 2003 American Institute of Physics.
Show PACS
77.55.-g Dielectric thin films
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.22.Ej Polarization and depolarization
68.65.Cd Superlattices

Voltage drop at interfaces in multilayer ferroelectrics

Xingjiao Li, Ningzhang Wang, Junbo Bao, Tao Chen, Jingping Xu, Hanhua Feng, and Shaoping Li

Appl. Phys. Lett. 82, 1589 (2003); http://dx.doi.org/10.1063/1.1556577 (3 pages)

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Based upon a defined surface barrier in ferroelectric multilayers deposited on (100) p-type silicon, ξVa, which bears a portion of the external electrical voltage, a modified empirical power law I = A(ξV)n is established for quantitatively describing detailed I–V dependence in ferroelectric multilayers. The voltage drop at the interface, Vi, which directly affects electrical characteristics of ferroelectric multiplayer system, is studied thoroughly. The voltage drop obtained from the modified empirical power law of the I–V dependence is consistent with that obtained from the C–V dependence model. © 2003 American Institute of Physics.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
73.40.Ns Metal-nonmetal contacts
77.55.-g Dielectric thin films
back to top
RSS Feeds

Combined scanning electrochemical atomic force microscopy for tapping mode imaging

A. Kueng, C. Kranz, B. Mizaikoff, A. Lugstein, and E. Bertagnolli

Appl. Phys. Lett. 82, 1592 (2003); http://dx.doi.org/10.1063/1.1559652 (3 pages) | Cited 24 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
With the integration of submicro- and nanoelectrodes into atomic force microscopy (AFM) tips using microfabrication techniques, an elegant approach combining scanning electrochemical microscopy (SECM) with atomic force microscopy has recently been demonstrated. Simultaneous imaging of topography and electrochemistry at a sample surface in AFM tapping mode with integrated SECM–AFM cantilevers oscillated at or near their resonance frequency is shown. In contrast to contact mode AFM imaging frictional forces at the sample surface are minimized. Hence, topographical and electrochemical information of soft surfaces (e.g., biological species) can be obtained. © 2003 American Institute of Physics.
Show PACS
07.79.Lh Atomic force microscopes
68.37.Ps Atomic force microscopy (AFM)
68.35.B- Structure of clean surfaces (and surface reconstruction)

Size dependence of lifetime and absorption cross section of Si nanocrystals embedded in SiO2

C. Garcia, B. Garrido, P. Pellegrino, R. Ferre, J. A. Moreno, J. R. Morante, L. Pavesi, and M. Cazzanelli

Appl. Phys. Lett. 82, 1595 (2003); http://dx.doi.org/10.1063/1.1558894 (3 pages) | Cited 64 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Photoluminescence lifetimes and optical absorption cross sections of Si nanocrystals embedded in SiO2 have been studied as a function of their average size and emission energy. The lifetimes span from 20 μs for the smallest sizes (2.5 nm) to more than 200 μs for the largest ones (7 nm). The passivation of nonradiative interface states by hydrogenation increases the lifetime for a given size. In contrast with porous Si, the cross section per nanocrystal shows a nonmonotonic behavior with emission energy. In fact, although the density of states above the gap increases for larger nanocrystals, this trend is compensated by a stronger reduction of the oscillator strength, providing an overall reduction of the absorption cross section per nanocrystal for increasing size. © 2003 American Institute of Physics.
Show PACS
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
61.46.-w Structure of nanoscale materials
78.55.Ap Elemental semiconductors
73.20.At Surface states, band structure, electron density of states
73.22.-f Electronic structure of nanoscale materials and related systems

The use of capillary force for fabricating probe tips for scattering-type near-field scanning optical microscopes

Yoshimasa Kawata, Seiji Urahama, Manambu Murakami, and Futoshi Iwata

Appl. Phys. Lett. 82, 1598 (2003); http://dx.doi.org/10.1063/1.1559441 (3 pages) | Cited 3 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a fabrication technique of a probe tip for scattering-type near-field microscopes. In the technique, capillary force is used to attach a metal particle at the apex of micropipettes. We can attach various kinds of particles, such as fluorescent particles, semiconductor particles, nonlinear materials, as well as metal particles. We have attached particles smaller than 180 nm in diameter. © 2003 American Institute of Physics.
Show PACS
81.16.Ta Atom manipulation
85.85.+j Micro- and nano-electromechanical systems (MEMS/NEMS) and devices
07.79.Fc Near-field scanning optical microscopes

Self-assembled vertical GaN nanorods grown by molecular-beam epitaxy

L. W. Tu, C. L. Hsiao, T. W. Chi, I. Lo, and K. Y. Hsieh

Appl. Phys. Lett. 82, 1601 (2003); http://dx.doi.org/10.1063/1.1558216 (3 pages) | Cited 57 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Dislocation-free vertical GaN pillars in nanoscale were grown on Si (111) surface through self-assembly by molecular-beam epitaxy. No extra catalytic or nanostructural assistance has been employed. These nanorods have a lateral dimension from ≲10 nm to ∼800 nm and a height of ≲50 nm to ≳3 μm protruding above the film, depending on the growth parameters. The top view of the nanorods has a hexagonal shape from scanning electron microscopy. Transmission electron microscopy shows that the nanorods are hexagonal, single crystal GaN along the c-axis. An extra peak at 363 nm originated from nanorods was observed in photoluminescence spectra at 66 K, which is ascribed to the surface states according to the results of surface passivation. Micro-Raman spectroscopy on a single nanorod reveals E1 and E2 modes at 559.0 and 567.4 cm−1, respectively. Large strain was observed in both the transmission electron micrograph and the Raman shift. A possible growth mechanism is discussed. © 2003 American Institute of Physics.
Show PACS
81.07.Bc Nanocrystalline materials
61.46.-w Structure of nanoscale materials
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
78.55.Cr III-V semiconductors
63.22.-m Phonons or vibrational states in low-dimensional structures and nanoscale materials
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
68.37.Hk Scanning electron microscopy (SEM) (including EBIC)
68.37.Lp Transmission electron microscopy (TEM)
73.22.-f Electronic structure of nanoscale materials and related systems
81.65.Rv Passivation
78.30.Fs III-V and II-VI semiconductors

Direct observation of inversely polarized frozen nanodomains in fatigued ferroelectric memory capacitors

E. L. Colla, I. Stolichnov, P. E. Bradely, and N. Setter

Appl. Phys. Lett. 82, 1604 (2003); http://dx.doi.org/10.1063/1.1559951 (3 pages) | Cited 27 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The direct observation of blocked polarization domains at the electrode–ferroelectric interface of electrically fatigued ferroelectric films is reported. Blocked nanodomains are believed to be the origin of polarization fatigue in ferroelectric nonvolatile memories but have not been directly observed so far due to the required upper metal electrode which impedes the direct access to the surface of the ferroelectric film. This problem has been solved by using low temperature melting metal as removable top electrode. After fatigue and subsequent top electrode removal it was possible to observe the polarization state of the fatigued capacitor and its depth profile by means of detection of the local piezoelectric activity with a conductive atomic force microscope tip. Blocked polarization domains with opposite polarization compared to the film body could be directly observed at the upper ferroelectrics surface. © 2003 American Institute of Physics.
Show PACS
84.32.Tt Capacitors
85.50.Gk Non-volatile ferroelectric memories
77.22.Ej Polarization and depolarization
77.55.-g Dielectric thin films
84.30.Sk Pulse and digital circuits
77.65.-j Piezoelectricity and electromechanical effects
77.80.Dj Domain structure; hysteresis

Ultraviolet laser treatment of multiwall carbon nanotubes grown at low temperature

J. S. Kim, K. S. Ahn, C. O. Kim, and J. P. Hong

Appl. Phys. Lett. 82, 1607 (2003); http://dx.doi.org/10.1063/1.1559654 (3 pages) | Cited 28 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Simple laser irradiation of well-aligned multiwall carbon nanotubes (MWCNTs) was performed to intentionally modify structural defects and to ablate possible contamination of the MWCNTs. Scanning electron microscopy and transmission electron microscopy confirmed the clear presence of the MWCNTs with open tips. A Raman spectra exhibited a decrease in an intensity ratio (ID/IG) of 1352 cm−1 (D band) over 1583 cm−1 (G band) peaks by significantly reducing the amorphous carbon phases of D band peaks. The structural improvement in the MWCNTs after optimum laser exposure resulted in a reduction of the turn-on voltage from 1.0 to 0.6 V/μm and an increase in the emission current. © 2003 American Institute of Physics.
Show PACS
61.82.Rx Nanocrystalline materials
61.46.-w Structure of nanoscale materials
78.67.Ch Nanotubes
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
78.30.Hv Other nonmetallic inorganics

Nanoscale molecular-switch devices fabricated by imprint lithography

Yong Chen, Douglas A. A. Ohlberg, Xuema Li, Duncan R. Stewart, R. Stanley Williams, Jan O. Jeppesen, Kent A. Nielsen, J. Fraser Stoddart, Deirdre L. Olynick, and Erik Anderson

Appl. Phys. Lett. 82, 1610 (2003); http://dx.doi.org/10.1063/1.1559439 (3 pages) | Cited 33 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Nanoscale molecular-electronic devices comprising a single molecular monolayer of bistable [2]rotaxanes sandwiched between two 40-nm metal electrodes were fabricated using imprint lithography. Bistable current–voltage characteristics with high on–off ratios and reversible switching properties were observed. Such devices may function as basic elements for future ultradense electronic circuitry. © 2003 American Institute of Physics.
Show PACS
81.16.Nd Micro- and nanolithography
81.07.Nb Molecular nanostructures
85.35.-p Nanoelectronic devices
85.65.+h Molecular electronic devices
73.61.Ph Polymers; organic compounds
72.80.Le Polymers; organic compounds (including organic semiconductors)
73.40.Sx Metal-semiconductor-metal structures
85.30.-z Semiconductor devices
84.32.Dd Connectors, relays, and switches
85.40.Hp Lithography, masks and pattern transfer
73.63.Rt Nanoscale contacts

In2O3 nanowires as chemical sensors

Chao Li, Daihua Zhang, Xiaolei Liu, Song Han, Tao Tang, Jie Han, and Chongwu Zhou

Appl. Phys. Lett. 82, 1613 (2003); http://dx.doi.org/10.1063/1.1559438 (3 pages) | Cited 168 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present an approach to use individual In2O3 nanowire transistors as chemical sensors working at room temperature. Upon exposure to a small amount of NO2 or NH3, the nanowire transistors showed a decrease in conductance up to six or five orders of magnitude and also substantial shifts in the threshold gate voltage. These devices exhibited significantly improved chemical sensing performance compared to existing solid-state sensors in many aspects, such as the sensitivity, the selectivity, the response time, and the lowest detectable concentrations. Furthermore, the recovery time of our devices can be shortened to just 30 s by illuminating the devices with UV light in vacuum. © 2003 American Institute of Physics.
Show PACS
85.35.-p Nanoelectronic devices
85.65.+h Molecular electronic devices
81.07.Vb Quantum wires
85.30.Tv Field effect devices
72.80.Jc Other crystalline inorganic semiconductors
07.07.Df Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing
61.46.-w Structure of nanoscale materials
73.21.Hb Quantum wires
73.63.Nm Quantum wires
82.80.-d Chemical analysis and related physical methods of analysis

A slit-type atom deflector with near-field light

Kouki Totsuka, Haruhiko Ito, Kiichi Suzuki, Kazuhiro Yamamoto, Motoichi Ohtsu, and Takashi Yatsui

Appl. Phys. Lett. 82, 1616 (2003); http://dx.doi.org/10.1063/1.1558222 (3 pages) | Cited 7 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We developed a near-field optical deflector for precise direction control of atomic motion using a dipole force. The blue-detuned, near-field light used to deflect atoms was generated near the edge of a 100-nm-wide slit and had a spatial distribution of 126 nm at a distance of 10 nm from the top edge. The deflection angle for a Rb atom was a function of light intensity, frequency detuning, and atomic velocity. © 2003 American Institute of Physics.
Show PACS
03.75.Be Atom and neutron optics
37.10.De Atom cooling methods
37.10.Gh Atom traps and guides
37.10.Vz Mechanical effects of light on atoms, molecules, and ions

Visible photoluminescence from nanostructured Si-based layers produced by air optical breakdown on silicon

A. V. Kabashin and M. Meunier

Appl. Phys. Lett. 82, 1619 (2003); http://dx.doi.org/10.1063/1.1557752 (3 pages) | Cited 17 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Pulsed radiation of CO2 laser has been used to produce an optical breakdown on a silicon target in atmospheric air. After several breakdown initiations near the threshold of plasma production, a highly porous layer was formed under the radiation spot on the silicon surface. The fabricated layers presented the porosity of 75%–80% and were formed of silicon nanocrystals imbedded in SiO2 matrix. They exhibited strong photoluminescence (PL) around 2.0 eV, which was stable to a prolonged continuous illumination of samples. Possible mechanisms of nanostructure formation and PL origin are discussed. © 2003 American Institute of Physics.
Show PACS
78.55.Mb Porous materials
78.67.Bf Nanocrystals, nanoparticles, and nanoclusters
68.47.Fg Semiconductor surfaces
81.07.Bc Nanocrystalline materials
61.46.-w Structure of nanoscale materials
81.05.Rm Porous materials; granular materials
77.22.Jp Dielectric breakdown and space-charge effects
79.20.Ds Laser-beam impact phenomena
78.55.Ap Elemental semiconductors

Molecular alignment enhancement phenomenon of polymer formed from a liquid crystal monomer in a liquid crystal solvent

Hideo Fujikake, Takeshi Murashige, Hiroto Sato, Masahiro Kawakita, and Hiroshi Kikuchi

Appl. Phys. Lett. 82, 1622 (2003); http://dx.doi.org/10.1063/1.1558221 (3 pages) | Cited 9 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report an abnormal alignment enhancement phenomenon of polymer molecules. The alignment order of a rigid-skeleton polymer made from a liquid crystalline monomer in a low-molecular-weight liquid crystal solvent was drastically enhanced with increasing temperature, even though the alignment order of the solution of the liquid crystal and monomer decreased. From polymer molecular alignment observations using polarizing Raman scattering microscopy, it was found that the polymer alignment order was three times greater than that of the original aligned monomer and polymer. This super alignment technique of polymer using a molecular-scaled self-assembly mechanism is applicable to the formation of electrically and/or optically functional nanopolymer wires. © 2003 American Institute of Physics.
Show PACS
61.41.+e Polymers, elastomers, and plastics
81.05.Lg Polymers and plastics; rubber; synthetic and natural fibers; organometallic and organic materials
82.35.-x Polymers: properties; reactions; polymerization
36.20.-r Macromolecules and polymer molecules
78.30.Jw Organic compounds, polymers
61.46.-w Structure of nanoscale materials
81.16.Fg Supramolecular and biochemical assembly
81.16.Be Chemical synthesis methods
81.16.Dn Self-assembly
81.05.Cy Elemental semiconductors

Structural and mechanical properties of nanostructured metalloceramic coatings on cobalt chrome alloys

Shane A. Catledge, Yogesh K. Vohra, S. Woodard, and R. Venugopalan

Appl. Phys. Lett. 82, 1625 (2003); http://dx.doi.org/10.1063/1.1560862 (3 pages) | Cited 6 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A functionally graded nanocrystalline metalloceramic coating on cobalt–chrome alloys was investigated with thin-film x-ray diffraction (XRD), nanoindentation, and scratch adhesion testing. The gradual transition in bonding from metallic to predominantly covalent along with a nanocrystalline grain structure provides a unique material system with excellent strength, toughness, and adhesion properties. XRD analysis of the (CrTiN) coating suggests a cubic sodium chloride phase structure with a = 4.2169±0.0035 Å. Nanoindentation measurements of the coating result in a hardness of 27 GPa and Young’s modulus of 320 GPa. The graded metallic/covalent nature of the coating with high plasticity also results in excellent film/substrate adhesion as shown by an average critical force of 44±5 N in scratch testing. © 2003 American Institute of Physics.
Show PACS
81.05.Bx Metals, semimetals, and alloys
62.20.Qp Friction, tribology, and hardness
81.40.Pq Friction, lubrication, and wear
68.60.Bs Mechanical and acoustical properties
81.65.-b Surface treatments
87.85.J- Biomaterials
61.46.-w Structure of nanoscale materials
62.25.-g Mechanical properties of nanoscale systems
62.20.M- Structural failure of materials
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
68.35.Np Adhesion
62.20.D- Elasticity
81.40.Jj Elasticity and anelasticity, stress-strain relations
62.20.F- Deformation and plasticity
81.40.Lm Deformation, plasticity, and creep
81.15.Jj Ion and electron beam-assisted deposition; ion plating
81.05.Je Ceramics and refractories (including borides, carbides, hydrides, nitrides, oxides, and silicides)
back to top
RSS Feeds

Oxygen induced p-doping of α-nickel phthalocyanine vacuum sublimed films: Implication for its use in organic photovoltaics

Thomas D. Anthopoulos and Torfeh S. Shafai

Appl. Phys. Lett. 82, 1628 (2003); http://dx.doi.org/10.1063/1.1559649 (3 pages) | Cited 29 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effects of oxygen doping on the charge transport and photovoltaic properties of α-nickel phthalocyanine (α-NiPc) based devices are investigated using in situ and ex situ I–V measurements. I–V characteristics for devices employing gold contacts indicate ohmic conduction at low voltages, followed by space-charge-limited conduction in higher fields. Upon exposure of NiPc to dry air an increase in the hole concentration (p0) from 8.5×1010 to 2.6×1015 m−3 is observed. When the top gold ohmic cathode is replaced by lead, Schottky type behavior is evident with the junction exhibiting photovoltaic effect. The energy conversion efficiency of the cell increases following exposure to oxygen. These results suggest that fabrication of air stable electronic devices based on NiPc is feasible. © 2003 American Institute of Physics.
Show PACS
73.40.Ns Metal-nonmetal contacts
73.50.Pz Photoconduction and photovoltaic effects
84.60.Jt Photoelectric conversion
61.72.up Other materials
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
73.61.Ph Polymers; organic compounds
73.30.+y Surface double layers, Schottky barriers, and work functions
73.50.Fq High-field and nonlinear effects
back to top
RSS Feeds

Nanomechanics of membrane tubulation and DNA assembly

T. Roopa and G. V. Shivashankar

Appl. Phys. Lett. 82, 1631 (2003); http://dx.doi.org/10.1063/1.1559632 (3 pages) | Cited 7 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report an interesting regime of tubule formation in multilamellar membrane vesicles. An optically trapped bead is used to apply a localized subpicoNewton force on a cationic vesicle to form a membrane tubule. The force extension curves reveal a saturation phase, with the tubule length extending up to tens of microns, beyond a threshold force 0.6±0.2 pN. We then use the tubule as a sensor for monitoring the dynamics of charge induced DNA integration on cationic membrane vesicles. Our results may also have applications in the development of nanowires and nanofluidic devices. © 2003 American Institute of Physics.
Show PACS
87.16.D- Membranes, bilayers, and vesicles
87.14.G- Nucleic acids
back to top
RSS Feeds

Coalescence of nanometer silver islands on oxides grown by filtered cathodic arc deposition

Eungsun Byon, Thomas W. H. Oates, and André Anders

Appl. Phys. Lett. 82, 1634 (2003); http://dx.doi.org/10.1063/1.1558955 (3 pages) | Cited 20 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Ultrathin silver films have been deposited on glass and oxide-coated glass using filtered cathodic arc deposition and, for comparison, magnetron sputtering. The energetic differences between these deposition methods lead to initially different film properties. Silver films made by cathodic arc deposition show an earlier onset of island coalescence, indicating a lower aspect ratio than islands produced by evaporation and sputtering. However, the as-deposited films are thermodynamically unstable, exhibiting changes on a timescale of minutes. While films of islands tend to increase their sheet resistance with time, the sheet resistance of contiguous films shows a decrease. Both effects can be explained by silver mobility driven to minimize film and interfacial energy. © 2003 American Institute of Physics.
Show PACS
68.55.-a Thin film structure and morphology
73.61.At Metal and metallic alloys
81.15.Kk Vapor phase epitaxy; growth from vapor phase

Point x-ray source using graphite nanofibers and its application to x-ray radiography

Takahiro Matsumoto and Hidenori Mimura

Appl. Phys. Lett. 82, 1637 (2003); http://dx.doi.org/10.1063/1.1558969 (3 pages) | Cited 32 times

Online Publication Date: 4 March 2003

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A point x-ray emission was obtained from a diode configuration composed of a graphite-nanofiber cold cathode and a conical-shaped copper metal anode. When combined with a highly sensitive charge coupled device (CCD) camera with a scintillator, this x-ray source was then used to obtain x-ray transmission images of a tungsten mesh and an x-ray test chart. The spatial resolution of this x-ray radiography system was on the order of 10 μm and the acquisition time for these images was less than 10 s. This combination of the point x-ray source and the sensitive detection system offers a high-resolution x-ray radiography system. © 2003 American Institute of Physics.
Show PACS
07.85.Fv X- and γ-ray sources, mirrors, gratings, and detectors
81.70.Ex Nondestructive testing: electromagnetic testing, eddy-current testing
84.47.+w Vacuum tubes
Page 2 of 2 Pages Previous Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close