Craig Pryor、M-E. Pistol、L. Samuelson1997-09-30arXiv
We calculate the electronic structure of nm scale InP islands embedded in $Ga_{0.51}In_{0.49}P$. The calculations are done in the envelope approximation and include the effects of strain, piezoelectric polarization, and mixing among 6 valence bands. The electrons are confined within the entire island, while the holes…
Mesoscale and Nanoscale PhysicsMaterials Science
Alessandra Geddo Lehmann、F. Kubel、H. Schmid1997-09-29Journal of Physics Condensed Matter
The structure of the complex perovskite (PFT), which belongs, according to the literature, to the ferroic species , has been refined by single-crystal and powder x-ray diffraction at room temperature, i.e. within the range of stability of the cubic phase. Attention has been paid to the possible presence of tetragonal…
Ferroelectric and Piezoelectric MaterialsMultiferroics and related materialsSolid-state spectroscopy and crystallography
Christian Stoffers、S. Yang、Fuping Zhang 等 6 位作者1997-09-29Applied Physics Letters
Cathodoluminescent phosphors excited at low voltages and high current densities often exhibit brightness saturation due to ground state depletion. A two-level model can be used to show that the luminance and saturation behavior of low voltage phosphors can be greatly improved by choosing phosphors with an activator de…
Luminescence Properties of Advanced Materials
S R Nair、V. K. Kondawar、S V Upadeo 等 5 位作者1997-09-29Journal of Physics Condensed Matter
phosphors find applications in dosimetry of ionizing radiations. Phosphors having Dy or Tm activators are high-sensitivity thermoluminescence dosimetry materials, while the phosphors with Eu or Sm activators are the proposed materials for radio-photoluminescence dosimetry. Mechanisms of several processes related to va…
Luminescence Properties of Advanced MaterialsRadiation Detection and Scintillator TechnologiesRadioactive Decay and Measurement Techniques
И. И. Власов、Victor Ralchenko、Е. Д. Образцова 等 5 位作者1997-09-29Applied Physics Letters
A confocal Raman spectroscopy was used to measure intrinsic stress distribution on the growth surface within individual grains of chemical-vapor-deposited diamond film. Polarization analysis of the Raman line shape revealed that even in high quality (2.8 cm−1 linewidth), free-standing film of 0.6 mm thickness, small r…
High-pressure geophysics and materialsDiamond and Carbon-based Materials ResearchForce Microscopy Techniques and Applications
Ji Wang、Jason Hector、Dominic Brady 等 8 位作者1997-09-29Applied Physics Letters
We report Cs halide-modified Ga–La sulfide glasses, a new class of chalcohalide glasses with improved fiber-drawing and optical properties suitable for Pr3+-doped fiber amplifiers at 1.3 μm. Cs halide-modified Ga–La sulfide glasses retain the essential characteristics of low phonon-energy and good rare-earth solubilit…
Luminescence Properties of Advanced MaterialsGlass properties and applicationsPhase-change materials and chalcogenides
Mitchell J. Labuda、John C. Wright1997-09-29Physical Review Letters
In order to determine the feasibility for a new family of nonlinear four-wave-mixing methods based on resonantly enhanced nuclear polarizations, the enhancement of a singly vibrationally resonant, nondegenerate, nonparametric process is measured using an interferometric method. The measurement shows that the resonant…
Advanced NMR Techniques and ApplicationsSolid-state spectroscopy and crystallographyMolecular spectroscopy and chirality
I. O. Troyanchuk、N. V. Samsonenko、N. Kasper 等 5 位作者1997-09-29Journal of Physics Condensed Matter
The magnetization measurement of systems with the nominal formula (R = Eu, Gd, Tb, Y) has been made. It has been found that and are weak ferromagnets of Dzialoshinsky - Moriya type whereas is an antiferromagnet. The substitution of manganese ions by cobalt ones leads to the appearance of different magnetic states: clu…
Magnetic and transport properties of perovskites and related materialsAdvanced Condensed Matter PhysicsSolid-state spectroscopy and crystallography
F.M. Schuurmans、Axel Schönecker、A.R. Burgers 等 4 位作者1997-09-29Applied Physics Letters
In this letter, we present a simplified evaluation method for light-biased photoconductance decay measurements. The measured effective lifetime is shown to be a differential quantity τeff,d, which may differ significantly from the actual effective lifetime τeff. However, the actual effective lifetime can be approximat…
Radiation Detection and Scintillator TechnologiesCalibration and Measurement TechniquesElectron and X-Ray Spectroscopy Techniques
Shining Zhu、Wenwu Cao1997-09-29Physical Review Letters
Direct observation of ferroelectric domain structures in LiTa${\mathrm{O}}_{3}$ crystal, without etching or surface coating, has been realized by using environmental scanning electron microscopy in secondary electron emission mode. The new method can nondestructively provide domain contrast image at submicron resoluti…
Ferroelectric and Piezoelectric MaterialsSemiconductor materials and devicesPhotorefractive and Nonlinear Optics
T. Hayashi、Masaaki Tanaka、Kan Seto 等 5 位作者1997-09-29Applied Physics Letters
III–V based magnetic (GaMnAs)/nonmagnetic(AlAs) semiconductor superlattices (SLs) have been grown by low-temperature molecular beam epitaxy. X-ray diffraction measurements show that the SLs have good crystalline quality and abrupt interfaces. The SLs having relatively wide (Ga,Mn)As layers (⩾70 Å) are found to be ferr…
Semiconductor Quantum Structures and DevicesZnO doping and propertiesElectronic and Structural Properties of Oxides
Thomas Garm Pedersen、Per Michael Johansen1997-09-29Physical Review Letters
A novel mean-field theory of photoinduced reorientation and optical anisotropy in liquid crystalline side-chain polymers is presented and compared with experiments. The reorientation mechanism is based on photoinduced $\mathrm{trans}\ensuremath{\leftrightarrow}\mathrm{cis}$ isomerization and a multidomain model of the…
Liquid Crystal Research AdvancementsAdvanced Materials and MechanicsAdvanced Physical and Chemical Molecular Interactions
J. S. Yin、Zhong Lin Wang1997-09-29Physical Review Letters
Self-assembling of size, shape, and phase controlled nanocrystals into superlattices with translational and even orientational ordering is a new approach for engineering nanocrystal materials and devices. High purity tetrahedral nanocrystals of CoO, with edge lengths of $4.4\ifmmode\pm\else\textpm\fi{}0.2$ nm, were sy…
ZnO doping and propertiesQuantum Dots Synthesis And PropertiesCopper-based nanomaterials and applications
Michael Kotelyanskii、Sanat K. Kumar1997-09-29arXiv
Thin films of binary mixtures that interact through isotropic forces and directionally specific "hydrogen bonding" are considered through Monte Carlo simulations. We show, in good agreement with experiment, that the single phase of these mixtures can be stabilized or destabilized on confinement. These results resolve…
Materials ScienceSoft Condensed Mattercond-mat.stat-mech
D. P. Chu、M. G. Dowsett1997-09-29arXiv
We demonstrate the use of maximum entropy based deconvolution to reconstruct boron spatial distribution from the secondary ion mass spectrometry (SIMS) depth profiles on a system of variously spaced boron $δ$-layers grown in silicon. Sample independent response functions are obtained using a new method which reduces t…
Materials Science
Silvio Franz、Giorgio Parisi1997-09-29Physical Review Letters
In the example of the spherical $p$-spin model, we study the phase diagram of glassy systems in the presence of an attractive coupling with a quenched configuration. We find competition among two phases, separated by a coexistence line terminating in a critical point, as in ordinary first-order phase transitions. We a…
Liquid Crystal Research AdvancementsMaterial Dynamics and PropertiesTheoretical and Computational Physics
Stephan Roche、Didier Mayou1997-09-29Physical Review Letters
We develop a new real-space method which allows one to evaluate the Kubo-Greenwood formula for dc conductivity of independent electrons in a static potential. We apply it to a numerical study of propagation modes in three dimensional quasiperiodic systems. These modes are strikingly different from those of periodic on…
Theoretical and Computational PhysicsQuantum chaos and dynamical systemsQuasicrystal Structures and Properties
Mehdi Asheghi、Yuet‐Kin Leung、S.S. Wong 等 4 位作者1997-09-29OpenAlex
Temperature fields in microdevices made from silicon-on-insulator (SOI) wafers are strongly influenced by the lateral thermal conductivity of the silicon overlayer, which is diminished by phonon scattering on the layer boundaries. This study measures the thermal conductivity of single-crystal silicon layers in SOI sub…
Semiconductor materials and devicesAdvancements in Semiconductor Devices and Circuit DesignThermal properties of materials
A. P. Ramirez1997-09-29OpenAlex
We review recent experimental work falling under the broad classification of colossal magnetoresistance (CMR), which is magnetoresistance associated with a ferromagnetic-to-paramagnetic phase transition. The prototypical CMR compound is derived from the parent compound, perovskite . When hole doped at a concentration…
Magnetic and transport properties of perovskites and related materialsRare-earth and actinide compoundsAdvanced Condensed Matter Physics
Igor Alexandrov、V. N. Serebryany、L. N. Sarvarova 等 5 位作者1997-09-28Texture Stress and Microstructure
It was shown that in ultrafine‐grained nanostructured Cu processed by severe plastic deformation and subjected to cold rolling and annealing, the level and character of Young′s modulus anisotropy is significantly different from values corresponding to cold rolled and annealed coarse‐grained Cu. The crystallographic te…
Microstructure and mechanical propertiesAluminum Alloy Microstructure PropertiesAluminum Alloys Composites Properties