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Strain distributions and interband transitions of CdxZn1-xTe/ZnTe asymmetric double quantum dots (DQDs) with different degree of coupling were calculated by using a three-dimensional finite difference method (FDM) taking into account strain and nonparabolicity effects. Bird’s-eye views of the truncated contour plots of the ground state wave functions at the conduction band of the Cd0.6Zn0.4Te/ZnTe DQDs showed the transition behavior from the coupling to the decoupling behaviors with increasing ZnTe spacer layer thickness. The interband transition energies from the ground electronic subband to the ground heavy-hole band (E1-HH1) in the CdxZn1-xTe/ZnTe DQDs, as determined from the FDM calculations, were in reasonable agreement with the experimental peaks of the temperature-dependent photoluminescence spectra corresponding to the (E1-HH1) interband transition energies in the temperature range from 32 to 130 K. [ABSTRACT FROM AUTHOR]

Interband transition energies and carrier distributions of the CdxZn1-xTe/ZnTe quantum wires (QWRs) were calculated by using a finite-difference method (FDM) taking into account shape-based strain effects. The shape of the CdxZn1-xTe/ZnTe QWRs was modeled to be approximately a half-ellipsoidal cylinder on the basis of the atomic force microscopy image. The excitonic peak energies corresponding to the ground electronic subband and the ground heavy-hole band (E1-HH1) at several temperatures, as determined from the FDM calculations taking into account strain effects, were in qualitatively reasonable agreement with those corresponding to the (E1-HH1) excitonic transition, as determined from the temperature-dependent photoluminescence spectra. [ABSTRACT FROM AUTHOR]

The structural properties and the shape of self-assembled CdTe/ZnTe quantum wires (QWRs) grown by using molecular beam epitaxy and atomic layer epitaxy were determined by using atomic force microscopy (AFM) measurements, and the interband transitions in the CdTe/ZnTe QWRs were investigated by using temperature-dependent photoluminescence (PL) measurements. The shape of the CdTe/ZnTe QWRs on the basis of the AFM image was modeled to be a half-ellipsoidal cylinder approximately. The temperature-dependent PL spectra showed that the PL peaks corresponding to the interband transitions from the ground electronic subband to the ground heavy-hole band (E1-HH1) shifted to lower energy with increasing temperature. Strain distributions and electronic subband energies at several temperatures were numerically calculated by using a finite-difference method (FDM) with and without taking into account shape-based strain and nonparabolicity effects. The excitonic peak corresponding to (E1-HH1) interband transitions, as determined from the PL spectra, was in reasonable agreement with that corresponding to the (E1-HH1) transitions obtained, as determined from the FDM calculations taking into account shape-based strain and nonparabolicity effects. The present results help improve understanding of the electronic structures of CdTe/ZnTe QWRs. [ABSTRACT FROM AUTHOR]

The microstructural properties and the shape of an InAs/GaAs array grown by molecular beam epitaxy were studied using transmission electron microscopy (TEM) measurements, and the interband transitions were investigated by using temperature-dependent photoluminescence (PL) measurements. The shape of the InAs quantum dots (QDs) on the basis of the cross-sectional bright-field TEM image was modeled to be a convex-plane lens. The electronic subband energies and the wave functions were numerically calculated by using a three-dimensional finite-difference method, taking into account strain effects. The excitonic peaks corresponding to interband transitions from the ground electronic subband to the ground heavy-hole band (E1-HH1) in the multiple-stacked QDs, as determined from the PL spectra, were in reasonable agreement with the (E1-HH1) interband transition energies obtained from the results of the numerical calculations. [ABSTRACT FROM AUTHOR]

Discusses a study which presented a mechanism derived from hydrodynamic theory to explain the ejection instability of liquid metal current collectors. Characterization of primary flow fields; Information on the primary flow instability at interface; Comparison of theoretically predicted and experimental ejection.