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

22 Mar 1999

Volume 74, Issue 12, pp. 1645-1775

Page 2 of 2 Pages Previous Page | Jump to Page
back to top
RSS Feeds

An ion-beam technique for measuring surface diffusion coefficients

P. M. DeLuca, J. G. C. Labanda, and S. A. Barnett

Appl. Phys. Lett. 74, 1719 (1999); http://dx.doi.org/10.1063/1.123666 (3 pages) | Cited 6 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The effective surface diffusion coefficient of Ga along the [110] direction on vicinal GaAs(001)2×4 surfaces during molecular-beam epitaxy was measured using specular ion current measurements. In this technique, 3 keV Ar ions were impinged upon the surface at a glancing angle (typically 3°), and the specularly scattered ion current was measured. Since specular reflections require a locally flat surface, adatoms cause a decrease in the measured current, allowing an average adatom density measurement. The time dependence of the Ga adatom population was measured during and after Ga deposition. Diffusion coefficients, obtained from the adatom lifetimes using a simple model of diffusion to the step edges, were fit well by the expression D = 2×10−9 exp(−0.73 eV/kT)cm2/s from 400 to 600 °C. © 1999 American Institute of Physics.
Show PACS
68.35.Fx Diffusion; interface formation
81.15.Hi Molecular, atomic, ion, and chemical beam epitaxy
79.20.Rf Atomic, molecular, and ion beam impact and interactions with surfaces

Stability of ultrathin semiconductor layers

Massimiliano Di Ventra

Appl. Phys. Lett. 74, 1722 (1999); http://dx.doi.org/10.1063/1.123667 (3 pages) | Cited 2 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The thermodynamical stability of ultrathin semiconductor layers embedded in isovalent bulk materials has been investigated by ab initio pseudopotential techniques. The AlAs/GaAs and GaAs/GaP structures have been chosen as prototypical examples for this study. We show that independently of the thin layers thickness: (i) At 0 K, the lattice-matched structures are thermodynamically more stable in the ideal configuration than in the case in which some Al and Ga atoms are allowed to diffuse forming a mixed plane; it is the finite-temperature entropy which finally favors the mixed configuration. Conversely, (ii) the lattice-mismatched structures are thermodynamically more stable in the mixed configuration than in the ideal one. In the latter case, it is mainly the chemical mixing and not the relaxation effects which favors diffusion. © 1999 American Institute of Physics.
Show PACS
68.60.Dv Thermal stability; thermal effects
71.15.Nc Total energy and cohesive energy calculations
66.30.Ny Chemical interdiffusion; diffusion barriers
68.35.Fx Diffusion; interface formation
71.15.Dx Computational methodology (Brillouin zone sampling, iterative diagonalization, pseudopotential construction)
71.15.Mb Density functional theory, local density approximation, gradient and other corrections
65.20.-w Thermal properties of liquids
65.40.gd Entropy

Thermal effect on current gains of an AlGaAs/GaAs heterostructure-emitter bipolar transistor

H. B. Lo, E. S. Yang, and Y. F. Yang

Appl. Phys. Lett. 74, 1725 (1999); http://dx.doi.org/10.1063/1.123668 (3 pages) | Cited 1 time

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The temperature effect on current gains is presented for an AlGaAs/GaAs heterostructure-emitter bipolar transistor (HEBT). Experimental results show that the HEBT has much less temperature sensitivity in current gain than a heterojunction bipolar transistor. The current gains for the HEBT are almost constant with the substrate temperature at a high current regime. This indicates that the HEBT could be a good candidate for power applications. © 1999 American Institute of Physics.  
Show PACS
79.40.+z Thermionic emission
85.30.Pq Bipolar transistors
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
73.61.Ey III-V semiconductors

Cathodoluminescence enhancement in porous silicon cracked in vacuum

J. Rams, B. Mendez, G. Craciun, R. Plugaru, and J. Piqueras

Appl. Phys. Lett. 74, 1728 (1999); http://dx.doi.org/10.1063/1.123669 (3 pages) | Cited 12 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An increase of the cathodoluminescence (CL) signal of porous silicon (PS) cracked in vacuum of up to three orders of magnitude has been achieved. Under high electron-beam currents, the samples cracked in interconnected pieces of tens of microns, exposing new surfaces to the electron beam. This treatment enhances the radiative intensity in PS associated with a broadband peaked at 720 nm, which is highly stable while the sample is kept in vacuum. Cross-sectional CL observations show that most of the light is generated in the top surface of the porous layer. The spectral depth dependence of the emitted light reveals a relatively weak blue emission in the region closer to the substrate. © 1999 American Institute of Physics.
Show PACS
78.60.Hk Cathodoluminescence, ionoluminescence
62.20.M- Structural failure of materials
81.40.Np Fatigue, corrosion fatigue, embrittlement, cracking, fracture, and failure

Time-resolved microwave technique for ultrafast charge-carrier recombination time measurements in diamonds and GaAs

S. V. Garnov, A. I. Ritus, S. M. Klimentov, S. M. Pimenov, V. I. Konov, S. Gloor, W. Lüthy, and H. P. Weber

Appl. Phys. Lett. 74, 1731 (1999); http://dx.doi.org/10.1063/1.123670 (3 pages) | Cited 11 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Recombination times of laser-excited charge carriers in natural diamond crystals, polycrystalline chemical vapor deposited (CVD) diamond films, and GaAs wafers were measured with 1 ns time resolution by a microwave-radiation technique. A waveguide scheme was applied to record time-dependent reflection and transmission of 140 GHz cw radiation. The measured recombination carrier lifetimes in the bulk of natural and CVD diamond samples were found to be of 1–3 ns. In GaAs, a distinguishing difference between the bulk (15 ns) and surface (3.5 ns) recombination times was observed. To validate the applicability of the developed technique, a computer simulation of the microwave-radiation interaction with excited plane–parallel specimens has been performed applying the Fabry–Perot resonator theory and the classical Drude model. © 1999 American Institute of Physics.
Show PACS
72.80.Cw Elemental semiconductors
73.61.Ey III-V semiconductors
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
73.50.Gr Charge carriers: generation, recombination, lifetime, trapping, mean free paths
78.66.Fd III-V semiconductors
72.40.+w Photoconduction and photovoltaic effects
73.50.Pz Photoconduction and photovoltaic effects
78.47.-p Spectroscopy of solid state dynamics
78.70.Gq Microwave and radio-frequency interactions

Femtosecond midinfrared-induced luminescence study of the ultrafast dynamics of split-off holes in GaAs

Kent C. Burr and C. L. Tang

Appl. Phys. Lett. 74, 1734 (1999); http://dx.doi.org/10.1063/1.123671 (3 pages) | Cited 7 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The ultrafast relaxation dynamics of split-off holes in GaAs are studied using a time-resolved two-wavelength excitation luminescence technique. Following valence-to-conduction-band transitions that are excited by near-infrared femtosecond pulses, delayed midinfrared femtosecond pulses are used to promote holes from the heavy-hole band to the split-off-hole band. The subsequent conduction-to-split-off-hole luminescence indicates that the room-temperature lifetime of split-off holes in GaAs is approximately 50 fs. The accompanying changes in conduction-to-heavy-hole-and-light-hole luminescence when holes are transferred to the split-off band are also observed. © 1999 American Institute of Physics.
Show PACS
78.55.Cr III-V semiconductors
78.47.-p Spectroscopy of solid state dynamics
71.20.Nr Semiconductor compounds
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
back to top
RSS Feeds

Large room-temperature intergrain magnetoresistance in double perovskite SrFe1−x(Mo or Re)xO3

T. H. Kim, M. Uehara, S-W. Cheong, and S. Lee

Appl. Phys. Lett. 74, 1737 (1999); http://dx.doi.org/10.1063/1.123672 (3 pages) | Cited 110 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We report significant intergrain magnetoresistance (IMR) in polycrystalline double perovskites of SrFe1−x(Mo or Re)xO3 at room temperature. Systematics of the temperature dependence of IMR indicates that the observed large room-temperature IMR in SrFe1/2Mo1/2O3 originates from the ferrimagnetic nature of insulating grain boundaries as well as the half-metallicity of this perovskite. Our results indicate that a new avenue for spin-polarized tunneling junctions is to utilize insulating interface layers with ferromagnetic or ferrimagnetic coupling. © 1999 American Institute of Physics.
Show PACS
75.47.Gk Colossal magnetoresistance
75.50.Gg Ferrimagnetics
75.30.Et Exchange and superexchange interactions
61.72.Mm Grain and twin boundaries
75.50.Dd Nonmetallic ferromagnetic materials
75.25.-j Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source x-ray scattering, etc.)

Dependence of magnetic properties on grain size of α-Fe in nanocomposite (Nd, Dy)(Fe, Co, Nb, B)5.5/α-Fe magnets

X. K. Sun, Jian Zhang, Yelong Chu, Wei Liu, Baozhi Cui, and Zhidong Zhang

Appl. Phys. Lett. 74, 1740 (1999); http://dx.doi.org/10.1063/1.123673 (3 pages) | Cited 37 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
For the nanocomposite magnets (Nd0.9Dy0.1)(Fe0.77Co0.12Nb0.03B0.08)5.5/α-Fe, the best magnetic properties were obtained with the average grain size of α-Fe d = 15 nm and with the content of α-Fe cm = 45 wt % that is well below the structural percolation threshold of the soft magnetic phase. The measured dependence of the coercivity on the grain size of α-Fe tends to indicate that the optimum grain size dop increases with increasing α-Fe content, for cm>30 wt %. If d>dop, contracted hysteresis is formed; if d<dop/2, the coercivity rapidly decrease due to possible coupling between hard magnetic grains situated at two sides of a soft grain. © 1999 American Institute of Physics.
Show PACS
75.50.Ww Permanent magnets
75.50.Kj Amorphous and quasicrystalline magnetic materials
81.40.Rs Electrical and magnetic properties related to treatment conditions
75.60.Ej Magnetization curves, hysteresis, Barkhausen and related effects
81.07.-b Nanoscale materials and structures: fabrication and characterization
75.50.Vv High coercivity materials
75.50.Bb Fe and its alloys

Epitaxial growth of magnetoresistive (00h), (0hh), and (hhh) La2/3Sr1/3MnO3 thin films on (001)Si substrates

J. Fontcuberta, M. Bibes, B. Martínez, V. Trtik, C. Ferrater, F. Sánchez, and M. Varela

Appl. Phys. Lett. 74, 1743 (1999); http://dx.doi.org/10.1063/1.123674 (3 pages) | Cited 10 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We show that suitable choice of the buffer heterostructure allows us to obtain epitaxial (00h), (0hh), and (hhh) La2/3Sr1/3MnO3 thin films on buffered Si(001) substrates. The magnetotransport properties are investigated. Irrespective of the film texture, it is found that the easy-magnetization direction lies within the film plane. The low-field magnetoresistance is mainly controlled by the in-plane misorientation of crystallites while differences associated with the distinct microstructure of the interfaces appear to have only a second-order effect. © 1999 American Institute of Physics.
Show PACS
81.15.Fg Pulsed laser ablation deposition
68.55.-a Thin film structure and morphology
73.50.Jt Galvanomagnetic and other magnetotransport effects (including thermomagnetic effects)
75.50.Dd Nonmetallic ferromagnetic materials
75.70.Ak Magnetic properties of monolayers and thin films
81.15.Kk Vapor phase epitaxy; growth from vapor phase
75.30.Kz Magnetic phase boundaries (including classical and quantum magnetic transitions, metamagnetism, etc.)

Single crystal superconductor nanowires by electrodeposition

Ge Yi and Walther Schwarzacher

Appl. Phys. Lett. 74, 1746 (1999); http://dx.doi.org/10.1063/1.123675 (3 pages) | Cited 81 times

Full Text: Read Online (HTML) | Download PDF


See Also: Erratum

Show Abstract
Superconducting Pb wires (diameter ∼ 50 nm) have been prepared by pulse electrodeposition in nanoporous membranes. Single crystal or polycrystalline nanowires may be grown selectively and reproducibly depending on the pulse parameters. Unexpectedly, the growth of single crystal wires requires a greater departure from equilibrium conditions (greater overpotential) than the growth of polycrystalline ones. The importance of controlling the crystal texture is demonstrated by measurements of the superconducting transition temperature Tc which give significantly different results for polycrystalline and single crystal nanowires. © 1999 American Institute of Physics.
Show PACS
74.78.-w Superconducting films and low-dimensional structures
74.70.Ad Metals; alloys and binary compounds (including A15, MgB2, etc.)
81.15.Pq Electrodeposition, electroplating
74.62.Bf Effects of material synthesis, crystal structure, and chemical composition
81.07.-b Nanoscale materials and structures: fabrication and characterization
74.25.F- Transport properties
68.55.-a Thin film structure and morphology

Domain structure in Fe-implanted Nd2Fe14B magnets

Youhui Gao, Jinghan Zhu, Yuqing Weng, and Baoshan Han

Appl. Phys. Lett. 74, 1749 (1999); http://dx.doi.org/10.1063/1.123676 (3 pages) | Cited 11 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The surface microstructure of Nd2Fe14B magnets was modified by Fe ion implantation. Their domain structures were studied by magnetic force microscopy. Corrugation and spike pattern domains were found on the (001) plane of unimplanted Nd2Fe14B. After implantation, a domain structure transition from complex maze to stripe pattern was found. The width of the stripe domain increases with increasing Fe dose. It indicates that the magnetic moments in the implanted layer turn out of their easy axis. The magnetization configurations in the implanted magnets were calculated using a micromagnetics method. The theoretical results agree well with the experimental results. © 1999 American Institute of Physics.
Show PACS
75.50.Ww Permanent magnets
75.50.Bb Fe and its alloys
75.60.Ch Domain walls and domain structure
61.80.Jh Ion radiation effects
61.72.up Other materials
75.40.Mg Numerical simulation studies
75.50.Kj Amorphous and quasicrystalline magnetic materials
back to top
RSS Feeds

Non-Arrhenius temperature dependence of reliability in ultrathin silicon dioxide films

D. J. DiMaria and J. H. Stathis

Appl. Phys. Lett. 74, 1752 (1999); http://dx.doi.org/10.1063/1.123677 (3 pages) | Cited 41 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The non-Arrhenius temperature dependence observed in the charge-to-breakdown data in thin oxides is related to the temperature dependence of the defect buildup in the same films. For each temperature, this defect buildup is studied as a function of the defect generation probability and the total number of defects at breakdown. Each of these quantities is shown to have its own unique temperature dependence, which when combined gives the results observed for the charge-to-breakdown data. As the oxide layers are made thinner, the temperature dependence of the defect generation probability dominates these observations. © 1999 American Institute of Physics.
Show PACS
85.30.Tv Field effect devices
77.22.Jp Dielectric breakdown and space-charge effects
77.55.-g Dielectric thin films
68.55.Ln Defects and impurities: doping, implantation, distribution, concentration, etc.
81.65.Mq Oxidation

Dielectric exchange: The key repulsive or attractive transient forces between atomic force microscope tips and charged surfaces

O. Teschke and E. F. de Souza

Appl. Phys. Lett. 74, 1755 (1999); http://dx.doi.org/10.1063/1.123678 (3 pages) | Cited 21 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Attractive as well as repulsive forces between electrically neutral tips and charged surfaces are measured directly with an atomic force microscope. The exchange of the volume of a region of the electric double layer of a mica surface immersed in water with a dielectric constant ϵDL by the tip with a dielectric constant ϵTip is responsible for the repulsion at large distances from the surface (starting at ∼100 nm, diffuse layer) and followed by an attraction when the tip is immersed in the Stern layer (∼2 nm). The force versus distance measured curves for high approaching velocities (⩾30 μm/s) were fitted to the expression of the dielectric exchange force derived by using a continuum theory for a sharpened pyramidal tip immersed in a spatially variable dielectric constant double-layer electric field. The dielectric exchange effect gives a consistent description of the force acting on the tip by assuming a double-layer region of disorganized water with ϵDL ∼ 80 at distances far away from the surface followed by a region of lower dielectric constant resulting from the alignment of the water molecules due to the mica surface charge. © 1999 American Institute of Physics.
Show PACS
73.30.+y Surface double layers, Schottky barriers, and work functions
07.79.Lh Atomic force microscopes
77.22.Ch Permittivity (dielectric function)
07.10.Pz Instruments for strain, force, and torque
back to top
RSS Feeds

A device layout for tunneling spectroscopy of barrier-separated electron systems with tunable dimensionality

G. Ploner, H. Hirner, T. Maier, G. Strasser, J. Smoliner, and E. Gornik

Appl. Phys. Lett. 74, 1758 (1999); http://dx.doi.org/10.1063/1.123679 (3 pages) | Cited 2 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A selective depletion scheme relying on self-aligned side gates is used to establish independent Ohmic contacts to two low-dimensional electron gases separated by a tunneling barrier. The self-aligned side gate technique is also demonstrated to be suitable for inducing an electrically tunable lateral confinement on the active region of the tunneling device via a central gate. As the central gate voltage is increased, the measured tunneling differential conductance clearly reveals a transition from tunneling between two-dimensional electron gases to tunneling between one-dimensional quantum wire states. The one-dimensional subband spacing of the collector electron channel could be continuously varied up to 6 meV. © 1999 American Institute of Physics.
Show PACS
73.61.Ey III-V semiconductors
73.21.-b Electron states and collective excitations in multilayers, quantum wells, mesoscopic, and nanoscale systems
73.40.Gk Tunneling
73.23.Hk Coulomb blockade; single-electron tunneling
85.35.Be Quantum well devices (quantum dots, quantum wires, etc.)

On-line laser photoacoustic detection of ethene in exhaled air as biomarker of ultraviolet radiation damage of the human skin

F. J. M. Harren, R. Berkelmans, K. Kuiper, S. te Lintel Hekkert, P. Scheepers, R. Dekhuijzen, P. Hollander, and D. H. Parker

Appl. Phys. Lett. 74, 1761 (1999); http://dx.doi.org/10.1063/1.123680 (3 pages) | Cited 22 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The exhaled air and volatile emission by the skin of human subjects were analyzed for traces of ethene (C2H4) by means of CO2 laser photoacoustic trace gas detection. Due to the extreme sensitivity of the detection system (6 part per trillion volume, 6:1012), these measurements could be performed on-line and noninvasively. Exhaled ethene was used as a biomarker for lipid peroxidation in the skin of human subjects exposed to ultraviolet (UV) radiation from a solarium. A change in the ethene concentration was already observed in the exhaled air after 2 min. Adaptation of the skin to UV exposure and direct skin emission could also be observed. © 1999 American Institute of Physics.
Show PACS
87.50.W- Optical/infrared radiation effects
87.15.M- Spectra of biomolecules
87.64.K- Spectroscopy
82.80.Ms Mass spectrometry (including SIMS, multiphoton ionization and resonance ionization mass spectrometry, MALDI)
87.15.R- Reactions and kinetics
back to top
RSS Feeds

Experimental time-domain study of THz signals from impulse excitation of a horizontal surface dipole

R. W. McGowan and D. Grischkowsky

Appl. Phys. Lett. 74, 1764 (1999); http://dx.doi.org/10.1063/1.123681 (3 pages) | Cited 4 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Using optoelectronic techniques with sub-ps resolution, we have characterized the electric-field time-domain response from an impulsively excited, micron-sized dipole antenna on a dielectric surface. When detected by an adjacent dipole antenna 400 μm distant, two primary signals are observed, a far-field pulse reflected from the back surface of the substrate and a surface-wave pulse. The surface-wave pulse appears as two distinct surface-propagating pulses despite originating from the dipole simultaneously. © 1999 American Institute of Physics.
Show PACS
84.40.Ba Antennas: theory, components and accessories
85.60.-q Optoelectronic devices
84.40.Az Waveguides, transmission lines, striplines

Multilayer thermionic cooler with a varying current density

R. Zhou, D. Dagel, and Y. H. Lo

Appl. Phys. Lett. 74, 1767 (1999); http://dx.doi.org/10.1063/1.123682 (3 pages) | Cited 2 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
A multilayer structure for thermionic cooling is proposed. This structure uses semiconductor heterojunctions for barriers and a varying current density across the junctions. Compared with the conventional multijunction thermionic cooler with a uniform current density, the design can yield a significantly higher temperature gradient, thus cooling more effectively. © 1999 American Institute of Physics.
Show PACS
85.80.Fi Thermoelectric devices
85.30.De Semiconductor-device characterization, design, and modeling
73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions

Pulse shaping using nonlinear dielectric SrTiO3

A. T. Findikoglu, D. W. Reagor, K. Ø. Rasmussen, A. R. Bishop, N. Grønbech-Jensen, Q. X. Jia, Y. Fan, and C. Kwon

Appl. Phys. Lett. 74, 1770 (1999); http://dx.doi.org/10.1063/1.124222 (3 pages) | Cited 4 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
We have studied electromagnetic pulse shaping in coplanar waveguide delay lines made from superconducting YBa2Cu3O7−δ electrodes on nonlinear dielectric SrTiO3 single-crystal substrates. The delay lines exhibited bias- and temperature-dependent nonlinearity and dispersion, with associated pulse-shaping effects. At low temperatures and under certain bias conditions, the interplay of dispersion and nonlinearity has led to stable and compact wave forms, reminiscent of microwave solitons. © 1999 American Institute of Physics.
Show PACS
84.40.Az Waveguides, transmission lines, striplines
85.50.-n Dielectric, ferroelectric, and piezoelectric devices
77.84.Ek Niobates and tantalates
77.84.Cg PZT ceramics and other titanates
85.25.Qc Superconducting surface acoustic wave devices and other superconducting devices
74.72.-h Cuprate superconductors

Positioning of self-assembled, single-crystal, germanium islands by silicon nanoimprinting

T. I. Kamins, D. A. A. Ohlberg, R. Stanley Williams, W. Zhang, and S. Y. Chou

Appl. Phys. Lett. 74, 1773 (1999); http://dx.doi.org/10.1063/1.123683 (3 pages) | Cited 38 times

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Strain energy from the lattice mismatch of a heteroepitaxial system can create “self-assembled,” single-crystal islands irregularly arranged on the surface. Alternatively, features of tens of nanometers can be patterned on a substrate by “nanoimprinting” using a mold and etching. When these two techniques are combined, the small patterned features can interact with the self-assembly process, causing the islands to form at the patterned features. The resulting regular array of very small islands may be useful for future devices. The positioning of single-crystal Ge islands by Si mesas formed by nanoimprinting and etching is demonstrated in this letter. © 1999 American Institute of Physics.
Show PACS
81.07.-b Nanoscale materials and structures: fabrication and characterization
81.16.-c Methods of micro- and nanofabrication and processing
85.35.-p Nanoelectronic devices
85.40.Hp Lithography, masks and pattern transfer
81.65.Cf Surface cleaning, etching, patterning
81.10.Fq Growth from melts; zone melting and refining
81.05.Cy Elemental semiconductors
Page 2 of 2 Pages Previous Page | Jump to Page
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close