When studying cosmology one is unavoidably faced with the problem of the relevance and meaning of the terms that are in use and any purely physical and mathematical discussion borders philosophy. In this respect we must move from the remark that any description of the cosmos needs the concepts of space and time. These two entities, so fundamental in physics, are indeed neither trivial nor obvio...

GaAs-based multiple quantum well (MQW) heterostructures comprised of metastable alloys such as GaAs1 ySby-GaAs1 zNz have potential for realizing high-performance and low temperature-sensitivity lasers in the 1.55 mm wavelength region. However, straininduced ‘lattice-latching’ and Sb-surface segregation effects limit the Sb-mole fractions in the pseudomorphically strained GaAs1 ySby layers to yp...

The electronic band structure and carrier density of strained armchair graphene nanoribbons (AGNRs) with widths of n =3 m and n =3 m +1 were examined using tight-binding approximation. The current-voltage (I-V) model of uniaxial strained n =3 m AGNRs incorporating quantum confinement effects is also presented in this paper. The derivation originates from energy dispersion throughout the entire ...

We report the successful growth oflnAs/Ga 1 _ x Inx Sb strained-layer superlattices by molecularbeam epitaxy. The superlattices are grown on thick, strain-relaxed InAs or GaSb buffer layers on ( 100)-oriented GaAs substrates. A short-period, heavily strained superlattice at the GaAs interface is found to improve the structural quality of the buffer layer. Arsenic incorporation in nominally pure...

In this article, we report the growth and characterization of InAsP/InP strained single quantum well (SSQW), strained single quantum well (SSQW) stack, and strained multiple quantum well (SMQW) structures on (1 0 0)-oriented InP substrates grown by metalorganic chemical vapor deposition. Double-crystal X-ray di!raction, photoluminescence (PL) and transmission electron microscope (TEM) are used ...

Based on the use of a multi-level mathematical model, this paper estimates stressed-strained state cylindrical reservoir in mounting joint and considers concentration stresses zone. The correctness selected model was verified to show that for an engineering assessment wall tank with variable thickness, it is possible ratios shell constant thickness. spread values no more than 1 %, which indicat...

A multi-level mathematical model was used to estimate the stressed-strained state of a cylindrical reservoir with defect in wall shape form dent; concentration stresses zone studied. The proper choice verified; it has been shown that engineering assessment tank variable thickness could employ ratios for shell constant thickness. spread values is 2?10 %. This indicates model, as well fact possib...

A toolkit that simplifies the calculation of solid-state elastic properties at finite temperatures to a one-shot task is developed. We report improvement and automation stress-strain method, which relies on averaged stresses from ab initio or classical calculations. Stresses obtained strained crystal lattices zero can be directly extracted fit strain-stress relationship get constants. Furthermo...

a r t i c l e i n f o Misfit defects in strained-SiGe layers grown on (100) Si-substrates by reduced pressure chemical vapor deposition (RPCVD) were investigated by using high-resolution X-ray diffraction (HRXRD) and transmission electron microscopy (TEM). While (004) omega rocking curve (ω-RC) is not sensitive to 60° misfit dislocations in a slightly strain-relaxed sample, they caused an asymm...