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

1 Nov 2004

Volume 85, Issue 18, pp. 3959-4247

Issue Cover Spotlight Figure

Appl. Phys. Lett. 85, 4142 (2004); http://dx.doi.org/10.1063/1.1811774 (3 pages)

Hong Jin Fan, Roland Scholz, Florian M. Kolb, and Margit Zacharias
Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds

Analysis of the intermolecular interaction of nanocomposites by THz spectroscopy

Naoto Nagai, Tomoko Imai, Ryoichi Fukasawa, Koya Kato, and Koji Yamauchi

Appl. Phys. Lett. 85, 4010 (2004); http://dx.doi.org/10.1063/1.1811795 (3 pages) | Cited 16 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Transmission and reflection measurements on polyamide nanocomposite films were performed in the THz frequency region, and the dielectric function was calculated using the Debye model to interpret the data. The relaxation time from the signal of orientation polarization due to the permanent dipole moments exhibits intermolecular interaction. In nanocomposites, the extreme increase of the interaction from polymer clay was first observed by THz spectroscopy. The essential interaction was thought to occur between the amide functional (−NH) group in polyamide-6 and the surface of the clay by considering the correlation with the results of infrared spectroscopy.
Show PACS
78.66.Sq Composite materials
78.70.Gq Microwave and radio-frequency interactions
78.30.Jw Organic compounds, polymers
78.66.Qn Polymers; organic compounds
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
81.05.Qk Reinforced polymers and polymer-based composites

Optical characteristics of 1.55 μm GaInNAs multiple quantum wells

H. D. Sun, A. H. Clark, H. Y. Liu, M. Hopkinson, S. Calvez, M. D. Dawson, Y. N. Qiu, and J. M. Rorison

Appl. Phys. Lett. 85, 4013 (2004); http://dx.doi.org/10.1063/1.1812371 (3 pages) | Cited 20 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report the optical characterization of high-quality 1.55 μm GaxIn1−xNyAs1−y multiquantum wells (MQWs), grown on GaAs with Ga(In)N0.01As spacer layers. The transitions between the quantized QW states of the electrons and holes have been identified using photoluminescence excitation spectroscopy. Their energies are consistent with theoretical fitting based on the band anticrossing model. It is also confirmed by detailed spectroscopic measurements that the addition of even a small amount of In to GaN0.01As barriers remarkably improves the optical characteristics of the QWs. The results imply that although strain-compensated GaInNAs MQWs provide a feasible approach to realizing 1.55 μm optical emission, the relative lattice mismatch between the wells and barriers is critical to the optical quality of the related QWs.
Show PACS
78.67.De Quantum wells
78.55.Cr III-V semiconductors

Sinusoidal phase grating created by a tunably buckled surface

Christopher Harrison, Christopher M. Stafford, Wenhua Zhang, and Alamgir Karim

Appl. Phys. Lett. 85, 4016 (2004); http://dx.doi.org/10.1063/1.1809281 (3 pages) | Cited 81 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We investigate a buckling instability by both small angle light scattering and atomic force microscopy, demonstrating that a tunable phase grating can be created with a mechanical instability. The instability is realized in a prestressed silicone sheet coated with a glassy polymer film. Compression of the sample results in a sinusoidally wrinkled surface where the amplitude is controlled by the degree of compression and the wavelength by film thickness. We model the system with Fourier optics, explaining the positions and relative intensities of the diffraction orders.
Show PACS
42.79.Dj Gratings
81.40.Lm Deformation, plasticity, and creep
62.20.F- Deformation and plasticity
68.37.Ps Atomic force microscopy (AFM)
42.30.Kq Fourier optics
68.60.Bs Mechanical and acoustical properties

Capillary kinetics of thin polymer films in permeable microcavities

Kahp Y. Suh, Pilnam Kim, and Hong H. Lee

Appl. Phys. Lett. 85, 4019 (2004); http://dx.doi.org/10.1063/1.1810212 (3 pages) | Cited 17 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a Poiseuille model that can explain the rate of capillary rise of thin polymer films in permeable microcavities. In comparison to the traditional Poiseuille formulation, two features of the system were considered: the permeable nature of the enclosure and the effect of thin polymer films that are confined to the substrate. The model predicts that the rate is inversely proportional to the channel width, contrary to what the original Poiseuille model predicts, and it is proportional to the initial film thickness, which the original model cannot account for. The modified model is in satisfactory agreement with experimental data.
Show PACS
83.80.Sg Polymer melts
47.11.-j Computational methods in fluid dynamics
68.15.+e Liquid thin films
47.15.Rq Laminar flows in cavities, channels, ducts, and conduits
47.50.-d Non-Newtonian fluid flows
83.50.Ha Flow in channels

Electronic structure and bonding properties of Si-doped hydrogenated amorphous carbon films

S. C. Ray, C. W. Bao, H. M. Tsai, J. W. Chiou, J. C. Jan, K. P. Krishna Kumar, W. F. Pong, M.-H. Tsai, W.-J. Wang, C.-J. Hsu, T. I. T. Okpalugo, P. Papakonstantinou, and J. A. McLaughlin

Appl. Phys. Lett. 85, 4022 (2004); http://dx.doi.org/10.1063/1.1812594 (3 pages) | Cited 11 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This work investigates the C K-edge x-ray absorption near-edge structure (XANES), valence-band photoelectron spectroscopy (PES), and Fourier transform infrared (FTIR) spectra of Si-doped hydrogenated amorphous carbon films. The C K-edge XANES and valence-band PES spectra indicate that the sp2∕sp3 population ratio decreases as the amount of tetramethylsilane vapor precursor increases during deposition, which suggest that Si doping% enhances sp3 and reduces sp2-bonding configurations. FTIR spectra show the formation of a polymeric sp3 C–Hn structure and Si–Hn bonds, which causes the Young’s modulus and hardness of the films to decrease with the increase of the Si content.
Show PACS
81.05.U- Carbon/carbon-based materials
68.60.Bs Mechanical and acoustical properties
71.23.-k Electronic structure of disordered solids
81.40.Jj Elasticity and anelasticity, stress-strain relations
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
79.60.Dp Adsorbed layers and thin films
78.70.Dm X-ray absorption spectra
78.35.+c Brillouin and Rayleigh scattering; other light scattering
79.60.Ht Disordered structures
78.66.Nk Insulators
62.20.D- Elasticity
62.20.Qp Friction, tribology, and hardness
61.72.S- Impurities in crystals
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.

Electroabsorption in single-crystal film of a second-order optical material

R. K. Swamy, S. P. Kutty, J. Titus, S. Khatavkar, and M. Thakur

Appl. Phys. Lett. 85, 4025 (2004); http://dx.doi.org/10.1063/1.1811772 (3 pages) | Cited 4 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
In this letter, we report results of electroabsorption and resonant electro-optic measurements in single-crystal film of 4′-dimethylamino-N-methyl-4-stilbazolium tosylate (DAST). The electroabsorption measurement was made by recording the changes in transmission through the film as an ac field was applied along the dipole axis. The electro-optic measurement was made using the field-induced birefringence method. The measurements were made in the absorptive domain, at 633 and 488 nm. The modulation (ΔT∕T) due to electroabsorption decreased as the angle between the incident polarization and the dipole axis was increased. The observed electroabsorption is due to the imaginary part of the electro-optic coefficient. The real part of the electro-optic coefficient (r11) as measured at 633 nm is 770 pm∕V. The imaginary parts of the electro-optic coefficients at 633 and 488 nm are 104 and 259 pm∕V, respectively.
Show PACS
78.20.Jq Electro-optical effects
78.20.Fm Birefringence
78.20.Ci Optical constants (including refractive index, complex dielectric constant, absorption, reflection and transmission coefficients, emissivity)
78.66.Qn Polymers; organic compounds
42.70.Jk Polymers and organics

Effects of the ratio of hardness to Young’s modulus on the friction and wear behavior of bilayer coatings

Wangyang Ni, Yang-Tse Cheng, Michael J. Lukitsch, Anita M. Weiner, Lenoid C. Lev, and David S. Grummon

Appl. Phys. Lett. 85, 4028 (2004); http://dx.doi.org/10.1063/1.1811377 (3 pages) | Cited 21 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We present a study of the effects of the ratio of hardness to Young’s modulus on the friction and wear behavior of layered composite coatings. Layered coating structures with the same surface coating but different interlayers were prepared by physical vapor deposition. We found that the ratio of hardness to Young’s modulus plays an important role in determining the friction coefficient and wear resistance of layered composite coatings. A low friction coefficient and high wear resistance can be achieved in structures with high ratio of hardness to Young’s modulus and moderately high hardness.
Show PACS
81.05.Bx Metals, semimetals, and alloys
68.60.Bs Mechanical and acoustical properties
68.55.A- Nucleation and growth
68.55.-a Thin film structure and morphology
68.35.Gy Mechanical properties; surface strains
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure
81.40.Jj Elasticity and anelasticity, stress-strain relations
81.40.Pq Friction, lubrication, and wear
62.20.Qp Friction, tribology, and hardness
62.20.D- Elasticity
81.15.Cd Deposition by sputtering

Thermoelastic generation of cylindrical Rayleigh waves and whispering gallery modes by pulsed-laser excitation

Wenxiang Hu, Menglu Qian, and John H. Cantrell

Appl. Phys. Lett. 85, 4031 (2004); http://dx.doi.org/10.1063/1.1809276 (3 pages) | Cited 3 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An analytical model of cylindrical surface waves excited thermoelastically by a pulsed-laser line source is presented. The laser-generated transient response of the cylindrical Rayleigh wave and the first three whispering gallery (WG) modes of an aluminum cylinder are calculated from the model using residue theory and the fast Fourier transform technique. The superposed wave form of the four transient modes is in excellent agreement with the wave form obtained from experiment and reveals that the peaks observed in experimental data are the result of wave-form interference from the superposition of all WG modes.
Show PACS
68.35.Iv Acoustical properties
78.20.hb Piezo-optical, elasto-optical, acousto-optical, and photoelastic effects

Study of the interaction of 4H–SiC and 6H–SiC(0001)Si surfaces with atomic nitrogen

Maria Losurdo, Maria M. Giangregorio, Giovanni Bruno, April Brown, and Tong-Ho Kim

Appl. Phys. Lett. 85, 4034 (2004); http://dx.doi.org/10.1063/1.1814438 (3 pages) | Cited 9 times

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The interaction of atomic nitrogen with 4H– and 6H–SiC(0001) Si-face surfaces is investigated. Clean and atomically smooth terraced surfaces obtained by in situ cleaning using atomic hydrogen have been exposed at 200 °C and 750 °C to atomic nitrogen produced by a rf remote N2 plasma. Spectroscopic ellipsometry is used for real-time monitoring of the kinetics of SiC surface modifications, and determining the thickness and properties of the nitrided layer. Surface potential measurements reveal the band bending of the nitrided SiC surface. An improvement in the heteroepitaxy of GaN on the low-temperature nitrided SiC surface is found.
Show PACS
81.65.Lp Surface hardening: nitridation, carburization, carbonitridation
81.65.Cf Surface cleaning, etching, patterning
68.35.B- Structure of clean surfaces (and surface reconstruction)
79.60.Bm Clean metal, semiconductor, and insulator surfaces
81.05.Hd Other semiconductors

Hydrogen-induced atomic deformation in SrBi2Nb2O9 perovskite structure

Ik Soo Kim, In-Hoon Choi, Yong Tae Kim, Seong-Il Kim, Dong Chul Yoo, and Jeong Yong Lee

Appl. Phys. Lett. 85, 4037 (2004); http://dx.doi.org/10.1063/1.1815064 (3 pages)

Online Publication Date: 3 November 2004

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The origin of hydrogen-induced structural deformation of ferroelectric SrBi2Nb2O9 (SBN) thin films is investigated by annealing in forming gas (3% H2–97% N2). High resolution transmission electron microscopy and fast Fourier transformation analysis reveal that the {115} planes are shifted upward and downward by 0.92 math along {115} plane after forming gas annealing, resulting in (00l) planes inclined by 9.54°. This shifted distance of 0.92 math means that the perovskite structure is distorted by 29.98% compared to the normal interatomic distance of 3.077 math. This distorted perovskite structure results in degradation of ferroelectric properties. However, this lattice deformation and ferroelectric property of SBN films are recovered after annealing in oxygen ambient.
Show PACS
77.80.Dj Domain structure; hysteresis
81.40.Gh Other heat and thermomechanical treatments
61.66.Fn Inorganic compounds
77.55.-g Dielectric thin films
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
81.40.Lm Deformation, plasticity, and creep
62.20.F- Deformation and plasticity
68.37.Lp Transmission electron microscopy (TEM)
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close