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

6 Sep 2004

Volume 85, Issue 10, pp. 1659-1861

Issue Cover Spotlight Figure

Appl. Phys. Lett. 85, 1793 (2004); http://dx.doi.org/10.1063/1.1790588 (3 pages)

Hyunsik Yoon, Kyoung Mi Lee, Dahl-Young Khang, Hong H. Lee, and Se-Jin Choi
Enlarge Image | Read More
Page 2 of 3 Pages Previous Page Next Page | Jump to Page
back to top
RSS Feeds

Transport properties of ordered-GalnP∕GaAs heterostructures

R. K. Ahrenkiel, W. Metzger, and D. F. Friedman

Appl. Phys. Lett. 85, 1733 (2004); http://dx.doi.org/10.1063/1.1784876 (3 pages)

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have studied the transport and recombination properties of Ga0.52In0.48P∕GaAs heterostructures by two transient techniques; Time-resolved photoluminescence and resonant coupled photoconductive decay. When the Ga0.52In0.48P is ordered, the two techniques produce radically different excess-carrier decay characteristics. These data can be explained by invoking a charge-separation mechanism at a type-II heterointerface. At higher excess-carrier injection levels, the charge-separation mechanism vanishes, and the type-I interface properties develop. These data are compatible with the polarization field model of ordered Ga0.52In0.48P.
Show PACS
78.67.Pt Multilayers; superlattices; photonic structures; metamaterials
78.55.Cr III-V semiconductors
73.61.Ey III-V semiconductors
73.50.Pz Photoconduction and photovoltaic effects
78.47.-p Spectroscopy of solid state dynamics
back to top
RSS Feeds

Enhanced Curie temperature of InMnP:Zn—TC∼300 K

Yoon Shon, H. C. Jeon, Y. S. Park, W. C. Lee, Seung Joo Lee, D. Y. Kim, H. S. Kim, H. J. Kim, T. W. Kang, Y. J. Park, Chong S. Yoon, and K. S. Chung

Appl. Phys. Lett. 85, 1736 (2004); http://dx.doi.org/10.1063/1.1790074 (3 pages) | Cited 5 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
P-type bulk InP was prepared by the liquid encapsulated Czochralski method and subsequently diffused with Mn by heat treatment after the evaporation of Mn on top of InP:Zn using a molecular beam epitaxy system. The characteristics of Mn-diffused InMnP:Zn were investigated by an energy dispersive x-ray spectroscopy, photoluminescence, and a superconducting quantum interference device magnetometer measurements. The samples were characterized by transmission electron microscopy and no evidence of secondary phase formation of InMnP:Zn was found. The results of energy dispersive x-ray peak displayed injected concentration of Mn near 3%. The results of photoluminescence measurement showed that optical broad transitions related to Mn appeared around 1.2 eV and it was confirmed that the transitions around 1.2 eV were Mn-related band by the diffusion of Mn into InP:Zn. Clear ferromagnetic hysteresis loops were observed at 10 and 300 K and the temperature-dependent magnetization showed ferromagnetic behavior around 300 K, which is caused by carrier-mediated ferromagnetism in InMnP:Zn. It is found that a ferromagnetic semiconductor at room temperature can be formed in diluted magnetic semiconductor based on GaMnN and InMnP additionally co-doped with Mg and Zn, respectively.
Show PACS
75.50.Pp Magnetic semiconductors
75.50.Dd Nonmetallic ferromagnetic materials
81.10.Fq Growth from melts; zone melting and refining
75.30.Kz Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
78.55.Cr III-V semiconductors
82.80.Ej X-ray, Mössbauer, and other γ-ray spectroscopic analysis methods
68.37.Lp Transmission electron microscopy (TEM)

Anisotropy of g-factor and electron spin resonance linewidth in modulation doped SiGe quantum wells

H. Malissa, W. Jantsch, M. Mühlberger, F. Schäffler, Z. Wilamowski, M. Draxler, and P. Bauer

Appl. Phys. Lett. 85, 1739 (2004); http://dx.doi.org/10.1063/1.1788881 (3 pages) | Cited 7 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigate the electron spin resonance of electrons in Si1−xGex quantum wells defined by SiGe barriers (19%–25%Ge). Adding small amounts of Ge changes both g-factor and linewidth and their anisotropy. We explain these effects in terms of the Bychkov–Rashba field that originates from one-sided modulation doping. The main effect arises from the increase in spin–orbit interaction with increasing x. We argue that these effects may be used to tune the g-factor of electrons in quantum dots for a selective spin manipulation.
Show PACS
73.63.Hs Quantum wells
71.70.Ej Spin-orbit coupling, Zeeman and Stark splitting, Jahn-Teller effect
76.30.Pk Conduction electrons
61.72.S- Impurities in crystals
71.18.+y Fermi surface: calculations and measurements; effective mass, g factor
81.70.Jb Chemical composition analysis, chemical depth and dopant profiling

Nonsymmetric current–voltage characteristics in ferromagnet∕superconductor thin film structures

N. Touitou, P. Bernstein, J. F. Hamet, Ch. Simon, L. Méchin, J. P. Contour, and E. Jacquet

Appl. Phys. Lett. 85, 1742 (2004); http://dx.doi.org/10.1063/1.1789231 (3 pages) | Cited 15 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We found that the current–voltage characteristics measured on La0.66Sr0.33MnO3∕YBa2Cu3O7−δ thin film heterostructures patterned as microbridges are nonsymmetric if the magnetization direction of the La0.66Sr0.33MnO3 film is in plane and perpendicular to the current direction. This effect is attributed to the contribution of the magnetic moment of this film to the vertical component of the field along the edges of the bridge. We suggest that this effect could find an application in the reading process of magnetic memories.
Show PACS
74.72.-h Cuprate superconductors
75.50.Dd Nonmetallic ferromagnetic materials
74.78.Fk Multilayers, superlattices, heterostructures
74.78.-w Superconducting films and low-dimensional structures
74.25.F- Transport properties
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
75.30.Cr Saturation moments and magnetic susceptibilities

Mössbauer effect probe of field-induced magnetic phase transition in LaFe13−xSix intermetallic compounds

Zhao-hua Cheng, Nai-li Di, Qing-an Li, Zhi-qi Kou, Zhi Luo, Xiao Ma, Guang-jun Wang, Feng-xia Hu, and Bao-gen Shen

Appl. Phys. Lett. 85, 1745 (2004); http://dx.doi.org/10.1063/1.1789235 (3 pages) | Cited 3 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Direct evidence of a field-induced magnetic phase transition in LaFe13−xSix intermetallics with a large magneticaloric effect was provided by 57Fe Mössbauer spectra in externally applied magnetic fields. Moreover, Mössbauer spectra demonstrate that a magnetic structure collinear to the applied field is abruptly achieved in LaFe11.7Si1.3 compound once the ferromagnetic state appears, showing a metamagnetic first-order phase transition. In the case of LaFe11.0Si2.0, the Fe magnetic moments rotate continuously from a random state to the collinear state with increasing applied field, showing that a second-order phase transition is predominant. The different types of phase transformation determine the magnetocaloric effects in response to temperature and field in these two samples.
Show PACS
75.50.Bb Fe and its alloys
76.80.+y Mössbauer effect; other γ-ray spectroscopy
75.30.Sg Magnetocaloric effect, magnetic cooling
75.30.Cr Saturation moments and magnetic susceptibilities
75.30.Kz Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)

Magnetic properties of magnetically isolated L10-FePt nanoparticles

Satoru Momose, Hiroyoshi Kodama, Takuya Uzumaki, and Atsushi Tanaka

Appl. Phys. Lett. 85, 1748 (2004); http://dx.doi.org/10.1063/1.1789238 (3 pages) | Cited 13 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This letter reports the results obtained by measuring the temperature dependence of the coercivity of magnetically isolated L10-FePt nanoparticles in agglomeration-free films deposited by using a dispersion stabilizer and a spin-coat technique. These measurements not only give the basic magnetic parameters of the nanoparticles but also provide information about the nanoparticle ordering process. The temperature at which isolated FePt nanoparticles start to order seems to be about 650°C.
Show PACS
75.50.Bb Fe and its alloys
75.50.Tt Fine-particle systems; nanocrystalline materials
75.70.Ak Magnetic properties of monolayers and thin films
81.40.Gh Other heat and thermomechanical treatments
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
61.46.-w Structure of nanoscale materials
81.07.Bc Nanocrystalline materials

Large magnetostriction in Fe100−xAlx (15⩽x⩽30) melt-spun ribbons

Z. H. Liu, G. D. Liu, M. Zhang, G. H. Wu, F. B. Meng, H. Y. Liu, L. Q. Yan, J. P. Qu, and Y. X. Li

Appl. Phys. Lett. 85, 1751 (2004); http://dx.doi.org/10.1063/1.1789242 (3 pages) | Cited 7 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Magnetostriction of Fe100−xAlx (15⩽x⩽30) al1oys has been largely improved by using melt-spun method. The large magnetostriction up to −700 ppm obtained in Fe81Al19 sample is about 5 times as large as that in conventional bulk samples of Fe–Al composition. It has been ascribed to the high concentration of Al–Al atom pairs created by melting-spinning method and their strongly preferential orientation in [100] textured ribbon plane. The remarkable anisotropic magnetostriction reflects the magnetoelastic competition occurring in those strong textured and thin ribbon samples. The composition dependence of the magnetostriction in ribbon samples has been found to be consistent with bulk materials.
Show PACS
75.50.Bb Fe and its alloys
75.80.+q Magnetomechanical effects, magnetostriction
75.70.Ak Magnetic properties of monolayers and thin films
75.30.Gw Magnetic anisotropy
68.55.-a Thin film structure and morphology
68.55.A- Nucleation and growth
68.60.Bs Mechanical and acoustical properties
back to top
RSS Feeds

Thickness scaling of polycrystalline Pb(Zr,Ti)O3 films down to 35 nm prepared by metalorganic chemical vapor deposition having good ferroelectric properties

Takahiro Oikawa, Hitoshi Morioka, Atsushi Nagai, Hiroshi Funakubo, and Keisuke Saito

Appl. Phys. Lett. 85, 1754 (2004); http://dx.doi.org/10.1063/1.1781354 (3 pages) | Cited 7 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Polycrystalline Pb(Zr0.35Ti0.65)O3 [PZT] films were prepared at 540°C by metalorganic chemical vapor deposition (MOCVD). Lower leakage and lower voltage-saturated 50-nm-thick PZT films were deposited on (111)Ir∕TiO2∕SiO2∕Si substrates than those on (111)Pt∕TiO2∕SiO2∕Si substrates. Moreover, low leakage current and good ferroelectricity were obtained for 35-nm-thick PZT films prepared on (111)Ir∕TiO2∕SiO2∕Si substrates by using source-gas-pulse-introduced MOCVD (pulsed-MOCVD) rather than conventional continuous gas supply MOCVD (continuous-MOCVD). As a result, 35-nm-thick PZT films with a Pr value of 47 μC∕cm2 at a maximum applied voltage of 1.2 V were obtained on (111)Ir∕TiO2∕SiO2∕Si substrates with pulsed-MOCVD. This opens the way for scaling down the film thickness of polycrystalline PZT films further while retaining good ferroelectricity.
Show PACS
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
77.55.-g Dielectric thin films
77.80.Dj Domain structure; hysteresis
81.15.Gh Chemical vapor deposition (including plasma-enhanced CVD, MOCVD, ALD, etc.)
77.22.Ej Polarization and depolarization
68.55.-a Thin film structure and morphology
68.55.A- Nucleation and growth

High-frequency surface acoustic wave device based on thin-film piezoelectric interdigital transducers

A. K. Sarin Kumar, P. Paruch, J.-M. Triscone, W. Daniau, S. Ballandras, L. Pellegrino, D. Marré, and T. Tybell

Appl. Phys. Lett. 85, 1757 (2004); http://dx.doi.org/10.1063/1.1787897 (3 pages) | Cited 23 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using high-quality epitaxial c-axis Pb(Zr0.2Ti0.8)O3 films grown by off-axis magnetron sputtering onto metallic (001) Nb-doped SrTiO3 substrates, a nonconventional thin-film surface acoustic wave device based on periodic piezoelectric transducers was realized. The piezoelectric transducers consist of a series of ferroelectric domains with alternating polarization states. The artificial modification of the ferroelectric domain structure is performed by using an atomic force microscope tip as a source of electric field, allowing local switching of the polarization. Devices with 1.2 and 0.8 μm wavelength, defined by the modulation period of the polarization, and corresponding to central frequencies in the range 1.50–3.50 GHz have been realized and tested.
Show PACS
43.38.Fx Piezoelectric and ferroelectric transducers
77.80.Dj Domain structure; hysteresis
77.22.Ej Polarization and depolarization
43.20.El Reflection, refraction, diffraction of acoustic waves
81.15.Cd Deposition by sputtering
77.80.Fm Switching phenomena

Silver solid solution piezoelectrics

Ilya Grinberg and Andrew M. Rappe

Appl. Phys. Lett. 85, 1760 (2004); http://dx.doi.org/10.1063/1.1787946 (3 pages) | Cited 18 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using density functional theory calculations, we investigate the feasibility of using silver on the perovskite A-site in high-performance lead-free piezoelectrics. The calculations show that silver atoms are ferroelectrically active and can off-center by 0.5 math. To induce Ag ferroelctric behavior absent in pure AgNbO3 we explore solid solutions of AgNbO3 with well-known simple perovskites PbTiO3, BaZrO3, and BaTiO3. For the AgNbO3–PbTiO3 solid solution, we predict a morphotropic phase boundary near (AgNbO3)3∕8(PbTiO3)5∕8. We find an unusual sequence of compositional phase transitions in AgNbO3–BaZrO3 and AgNbO3–BaTiO3 which are due to the effects of volume expansion in perovskites. For the AgNbO3–BaTiO3 solid solution we find two morphotropic phase boundaries at 12.5% and 37.5% AgNbO3 compositions with favorable piezoeletric properties and indications of high TC.
Show PACS
77.80.B- Phase transitions and Curie point
77.65.-j Piezoelectricity and electromechanical effects
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
71.15.Mb Density functional theory, local density approximation, gradient and other corrections
81.30.Dz Phase diagrams of other materials

Double minimum in the surface stabilized ferroelectric liquid crystal switching response

C. V. Brown, J. M. Hind, K. P. Lymer, and J. C. Jones

Appl. Phys. Lett. 85, 1763 (2004); http://dx.doi.org/10.1063/1.1786365 (3 pages)

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A double minimum has recently been observed in the time–voltage switching response for a smectic C* liquid crystal layer in the surface stabilized geometry (“Ferroelectric Liquid Crystal Device,” K. P. Lymer and J. C. Jones, U.K. Patent No. GB2338797, 17th June 1999). Liquid crystal continuum theory is used to demonstrate that this unusual switching behavior arises if the equilibrium orientation of the molecular director rotates around the smectic cone as a function of distance through one half of the layer only. The double minimum is shown to evolve for large differences between the ε2 and ε1 components of the smectic C biaxial permittivity tensor.
Show PACS
77.84.Nh Liquids, emulsions, and suspensions; liquid crystals
77.80.Fm Switching phenomena
61.30.Hn Surface phenomena: alignment, anchoring, anchoring transitions, surface-induced layering, surface-induced ordering, wetting, prewetting transitions, and wetting transitions
78.20.Jq Electro-optical effects
61.30.Dk Continuum models and theories of liquid crystal structure
61.30.Gd Orientational order of liquid crystals; electric and magnetic field effects on order
68.15.+e Liquid thin films
77.22.Ch Permittivity (dielectric function)
78.68.+m Optical properties of surfaces
back to top
RSS Feeds

Tribonanolithography of silicon in aqueous solution based on atomic force microscopy

Jeong Woo Park, Noritaka Kawasegi, Noboru Morita, and Deug Woo Lee

Appl. Phys. Lett. 85, 1766 (); http://dx.doi.org/10.1063/1.1773620 (3 pages) | Cited 14 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The tribonanolithography (TNL) of silicon substrate in aqueous solution based on the use of atomic force microscopy is demonstrated. A specially designed cantilever with a diamond tip, which allows the formation of a protruding oxide layer several nanometers high using a simple machining process with a given pitch, was applied to the TNL process in KOH solution instead of a conventional silicon cantilever. The anisotropic wet etching stopped in the modified area because silicon oxide was resistant to corrosion by KOH. The fabrication of a three-dimensional slant nanostructure is possible by taking advantage of the time lag of oxide formation during etching in KOH solution.
Show PACS
81.07.Bc Nanocrystalline materials
81.16.Nd Micro- and nanolithography
81.65.Cf Surface cleaning, etching, patterning
61.46.-w Structure of nanoscale materials
68.35.B- Structure of clean surfaces (and surface reconstruction)

Temperature-dependent studies of Y-junction carbon nanotube electronic transport

C. Papadopoulos, A. J. Yin, and J. M. Xu

Appl. Phys. Lett. 85, 1769 (2004); http://dx.doi.org/10.1063/1.1787592 (3 pages) | Cited 9 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Electronic transport in Y-junction carbon nanotubes was examined as a function of temperature. Rectifying behavior was observed from 10 to 300 K with the conductance displaying power-law dependencies on temperature and applied bias. The data are consistent with models for tunneling between two tube segments but display asymmetric exponents depending on bias polarity. The conductance asymmetry is found to be essentially independent of temperature and can be understood from the lack of inversion symmetry of the Y-junction geometry, which creates a unique type of mesoscopic rectification for current flow in the nonlinear response regime.
Show PACS
73.63.Fg Nanotubes
73.63.Rt Nanoscale contacts
73.40.Ns Metal-nonmetal contacts
73.40.Ei Rectification

Pentacene field-effect transistors with sub-10-nm channel lengths

Liang Wang, Daniel Fine, Taeho Jung, Debarshi Basu, Heinz von Seggern, and Ananth Dodabalapur

Appl. Phys. Lett. 85, 1772 (2004); http://dx.doi.org/10.1063/1.1790033 (3 pages) | Cited 39 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The field effect in pentacene thin-film transistors was studied using bottom-contact devices with channel lengths below 10 nm. To suppress spreading current in these devices, which have a small channel width-to-length (W-L) ratio, we employed a pair of guarding electrodes as close as 20 nm to the two sides of the channel. The responses of these nanometer scale transistors exhibit good gate modulation. Mobilities of 0.046 cm2∕Vs and on/off ratios of 97 were achieved in sub-10-nm transistors. We find that the device response is strongly influenced by the nature of the metal-semiconductor contact.
Show PACS
85.30.Tv Field effect devices
73.61.Ph Polymers; organic compounds
73.40.Ns Metal-nonmetal contacts
72.20.Fr Low-field transport and mobility; piezoresistance
73.50.Dn Low-field transport and mobility; piezoresistance

Reinforcement and rupture behavior of carbon nanotubes–polymer nanofibers

Haihui Ye, Hoa Lam, Nick Titchenal, Yury Gogotsi, and Frank Ko

Appl. Phys. Lett. 85, 1775 (2004); http://dx.doi.org/10.1063/1.1787892 (3 pages) | Cited 64 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
High-resolution transmission electron microscopy examination of carbon nanotube–polyacrylonitrile composite fibers synthesized by electrospinning was conducted. Both single-wall carbon nanotubes and multi-wall carbon nanotubes have been used to reinforce the polymer fibers. A two-stage rupture behavior of the composite fibers under tension, including crazing of polymer matrix and pull-out of carbon nanotubes, has been observed. Carbon nanotubes reinforce the polymer fibers by hindering crazing extension, reducing stress concentration, and dissipating energy by pullout. Distribution of nanotubes in the polymer matrix and interfacial adhesion between nanotubes and polymers are two major factors to determine the reinforcement effect of carbon nanotubes in polymer fibers.
Show PACS
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
62.20.M- Structural failure of materials
61.46.-w Structure of nanoscale materials
81.07.De Nanotubes
81.05.ub Fullerenes and related materials
81.05.Qk Reinforced polymers and polymer-based composites
82.35.Gh Polymers on surfaces; adhesion

Molecular dynamics simulations of bending behavior of tubular graphite cones

P. Liu, Y. W. Zhang, and C. Lu

Appl. Phys. Lett. 85, 1778 (2004); http://dx.doi.org/10.1063/1.1787894 (3 pages) | Cited 2 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF


See Also: Erratum

Show Abstract
Molecular dynamics simulations are performed to investigate the bending behavior of tubular graphite cones (TGCs). The second-generation reactive bond-order potential and four different van der Waals potentials are used to describe bonding and nonbonding atomic interactions, respectively. It is shown that the bending behavior is insensitive to the choice of the van der Waals potentials. An increase in the cone apex angle of TGCs moderately improves the bending stiffness due to the low shear resistance between the nanotube walls. A TGC with a high cone apex angle is preferred to a TGC with a low cone apex angle in terms of bending stiffness and stress level. It is also shown that an increase in the diameter of the innermost nanotube effectively increases the bending stiffness of TGCs.
Show PACS
61.46.-w Structure of nanoscale materials
81.40.Lm Deformation, plasticity, and creep
62.20.F- Deformation and plasticity
62.20.D- Elasticity
81.40.Jj Elasticity and anelasticity, stress-strain relations

Si-capping of Ge nanohuts on Si(001) analyzed by scanning tunneling microscopy and the finite element method

I. Goldfarb, L. Banks-Sills, and R. Eliasi

Appl. Phys. Lett. 85, 1781 (2004); http://dx.doi.org/10.1063/1.1787958 (3 pages) | Cited 4 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Ge hut nanocrystals were grown on an Si(001) surface and Si-capped by gas-source molecular-beam epitaxy. Growth and capping at 430 °C were observed in real time by scanning tunneling microscopy, and analyzed by the finite element method. Observations made here of three-dimensional Si-cap growth (in the shape of pyramids and huts) on Ge, similar to the Ge growth on Si(001), are consistent with energetic arguments based on finite elements in the framework of linear elasticity. These observations are in contrast with the higher-temperature behavior, where Si preferentially sticks to the Ge nanocrystal facets, causing them to develop large flat (001) tops and a reduced height-base ratio.
Show PACS
81.05.Cy Elemental semiconductors
68.47.Fg Semiconductor surfaces
68.37.Ef Scanning tunneling microscopy (including chemistry induced with STM)
61.46.-w Structure of nanoscale materials
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy

Manipulating the size distributions of quantum dots associated with strain-renormalized surface energy

T. P. Munt, D. E. Jesson, V. A. Shchukin, and D. Bimberg

Appl. Phys. Lett. 85, 1784 (2004); http://dx.doi.org/10.1063/1.1787943 (3 pages) | Cited 6 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Utilizing computer simulations based on a continuity equation model, we propose a strategy for modifying three-dimensional quantum dot size distributions using a two-stage growth and anneal approach. The method simply requires that individual quantum dots have a minimum in their chemical potential as a function of island size, such as those associated with strain-renormalized surface energy. By depositing material for the required time, the island size distribution can be tuned to a desired size before removing the flux to narrow the distribution.
Show PACS
81.07.Ta Quantum dots
68.35.Md Surface thermodynamics, surface energies
65.40.G- Other thermodynamical quantities
68.35.B- Structure of clean surfaces (and surface reconstruction)

Buckling instabilities in multiwalled carbon nanotubes under uniaxial compression

J. F. Waters, L. Riester, M. Jouzi, P. R. Guduru, and J. M. Xu

Appl. Phys. Lett. 85, 1787 (2004); http://dx.doi.org/10.1063/1.1790602 (3 pages) | Cited 30 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report experimental observations of shell buckling instabilities in freestanding, vertically aligned multiwalled carbon nanotubes subjected to uniaxial compression. Highly ordered and uniform arrays of carbon nanotubes embedded in an alumina matrix were fabricated and subjected to uniaxial compression using a nanoindenter. The buckling load was found to be on the order of 2 μN for nanotubes with 25 nm outer radius, 13 nm inner radius, and heights of 50 and 100 nm. Good agreement was found between the experimental observations and the predictions of linear elastic shell buckling theory.
Show PACS
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
62.20.M- Structural failure of materials
61.46.-w Structure of nanoscale materials
62.25.-g Mechanical properties of nanoscale systems
81.40.Lm Deformation, plasticity, and creep
62.20.F- Deformation and plasticity
81.40.Jj Elasticity and anelasticity, stress-strain relations
68.35.Gy Mechanical properties; surface strains

Observation of cold atom output from an evanescent-light funnel

Akifumi Takamizawa, Haruhiko Ito, Shungo Yamada, and Motoichi Ohtsu

Appl. Phys. Lett. 85, 1790 (2004); http://dx.doi.org/10.1063/1.1786362 (3 pages) | Cited 6 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the demonstration of an atom funnel composed of evanescent light. The flux intensity of cold Rb atoms output from a 240 μm exit hole was 7×107 atom∕cm2 s at a blue detuning of 1.2 GHz. Sisyphus cooling doubled the output efficiency. The estimated flux intensity was 1012 atom∕cm2 s when the exit-hole diameter was 110 μm.
Show PACS
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

Rapid flash patterning of nanostructures

Hyunsik Yoon, Kyoung Mi Lee, Dahl-Young Khang, Hong H. Lee, and Se-Jin Choi

Appl. Phys. Lett. 85, 1793 (2004); http://dx.doi.org/10.1063/1.1790588 (3 pages) | Cited 9 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Sub-100 nm structures can be fabricated in tens of seconds with an aspect ratio much larger than unity by the general purpose patterning method presented here. A flexible film mold and a rapid flash heating with an infrared lamp are used in this nonphotolithographic patterning technique. Unlike other unconventional methods, the substrate surface can be made exposed and the resulting pattern height is sufficiently high for subsequent etching of the substrate.
Show PACS
81.16.Rf Micro- and nanoscale pattern formation
68.55.-a Thin film structure and morphology
61.82.Pv Polymers, organic compounds
61.80.Ba Ultraviolet, visible, and infrared radiation effects (including laser radiation)
81.65.Cf Surface cleaning, etching, patterning

Synthesis and electrical properties of carbon nanotube polyaniline composites

Yunze Long, Zhaojia Chen, Xuetong Zhang, Jin Zhang, and Zhongfan Liu

Appl. Phys. Lett. 85, 1796 (2004); http://dx.doi.org/10.1063/1.1786370 (3 pages) | Cited 37 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A multiwalled carbon nanotube∕polyaniline composite with cablelike morphology has been synthesized by an in situ chemical oxidative polymerization directed with cationic surfactant cetyltrimethylammonium bromide. It is interestingly found that with increasing carbon nanotube loading from 0 to 24.8 wt%, the conductivity increases by two orders of magnitude and the Mott’s characteristic temperature T0 which depends on the hopping barrier decreases by three orders of magnitude. Furthermore, the low-temperature magnetoresistance has also changed the sign from positive to negative. The results reveal a strong coupling between the carbon nanotube and the tightly coated polymer chains, which enhances the average localization length and the electronic properties of the composites.
Show PACS
81.05.Qk Reinforced polymers and polymer-based composites
82.35.-x Polymers: properties; reactions; polymerization
72.80.Tm Composite materials
72.20.Ee Mobility edges; hopping transport
78.30.-j Infrared and Raman spectra
75.47.Pq Other materials

Ultrafast absorptive and refractive nonlinearities in multiwalled carbon nanotube films

H. I. Elim, W. Ji, G. H. Ma, K. Y. Lim, C. H. Sow, and C. H. A. Huan

Appl. Phys. Lett. 85, 1799 (2004); http://dx.doi.org/10.1063/1.1786371 (3 pages) | Cited 28 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
By using femtosecond laser pulses at a wavelength range from 720 to 780 nm, we have observed absorptive and refractive nonlinearities in a film of multiwalled carbon nanotubes grown mainly along the direction perpendicular to the surface of quartz substrate. The z-scans show that both absorptive and refractive nonlinearities are of negative and cubic nature in the laser irradiance range from a few to 300 GW∕cm2. The magnitude of the third-order nonlinear susceptibility, χ(3), is of an order of 10−11 esu. The degenerate pump–probe measurement reveals a relaxation time of ∼2 ps.
Show PACS
78.67.Ch Nanotubes
42.65.An Optical susceptibility, hyperpolarizability
78.40.Ri Fullerenes and related materials
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.47.-p Spectroscopy of solid state dynamics

Synthesis of semiconductor nanowires by annealing

C. Y. Zhi, X. D. Bai, and E. G. Wang

Appl. Phys. Lett. 85, 1802 (2004); http://dx.doi.org/10.1063/1.1786374 (3 pages) | Cited 8 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Semiconductor nanowires, such as InAs, InP, β-Ga2O3, and GaP are synthesized by annealing semiconductor wafers covered with Au film at an appropriate temperature in the region of 550°–650°C in a N2 atmosphere. The composition of the resulting semiconductor nanowires is determined by both the substrate and the chemical conditions of growth. High-resolution transmission electron microscopy and selected area electron diffraction reveal high degrees of crystallization of the as-grown nanowires. The characteristics of the annealing method for synthesis of semiconductor nanowires are discussed.
Show PACS
81.05.Ea III-V semiconductors
81.07.Bc Nanocrystalline materials
61.46.-w Structure of nanoscale materials
68.65.-k Low-dimensional, mesoscopic, nanoscale and other related systems: structure and nonelectronic properties
61.72.Cc Kinetics of defect formation and annealing
68.35.B- Structure of clean surfaces (and surface reconstruction)
64.70.K- Solid-solid transitions
82.80.Ej X-ray, Mössbauer, and other γ-ray spectroscopic analysis methods
81.40.Gh Other heat and thermomechanical treatments
81.15.Cd Deposition by sputtering

Thin film transistors fabricated by in situ growth of SnO2 nanobelts on Au∕Pt electrodes

Q. H. Li, Y. J. Chen, Q. Wan, and T. H. Wang

Appl. Phys. Lett. 85, 1805 (2004); http://dx.doi.org/10.1063/1.1789232 (3 pages) | Cited 9 times

Online Publication Date: 13 September 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Thin film transistors are fabricated by in situ growth of SnO2 nanobelts on Au∕Pt electrodes. A linear correlation in the output characteristics is observed at zero gate voltage, indicating Ohmic contacts between the nanobelts and the electrodes. The transistors exhibit n-type behaviors and have a mobility of 1.85 cm2∕V s with a current on∕off ratio above 103. The conductance increases as the pressure in the device chamber is reduced, which indicates that the transistors are promising for oxygen detecting.
Show PACS
85.30.Tv Field effect devices
61.46.-w Structure of nanoscale materials
73.40.Ns Metal-nonmetal contacts
73.50.Dn Low-field transport and mobility; piezoresistance
81.16.Nd Micro- and nanolithography
81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
Page 2 of 3 Pages Previous Page Next Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close