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By cutting electro-deposited nickel plates at different angles between the rolling planes and the growth plane, we obtained bulk samples with different initial textures. We investigated the microstructures, macrotextures, and microhardness of such samples before and after cold rolling. The results showed that the samples cut at different angles have different initial textures before the cold rolling, and their microstructures changed from isotropic crystals to columnar ones as the cutting angle increased. After cold rolling, the deformed microstructures textures were the same. However, the microhardness of the material was closely related to the cutting angle. As the cutting angle increased, the microhardness decreased significantly. This phenomenon is associated with the dimensional differences between the axial and horizontal directions of the columnar crystal grains of the electro-deposited materials.

We report a theoretical investigation of the strain effects on the electronic energy band in a GaAs-In0.25Ga0.75As-Al0.5Ga0.5As asymmetric quantum wire formed in a V-grooved substrate. Our model is based on the sp3s* tight-binding model. It includes different spatial distributions of the lattice-mismatch-induced strain. We solve numerically the tight-binding Hamiltonian through the local Green's function from which the electronic local density of states (LDOS) is obtained. The detailed energy band structure (discrete localized states and energy bands of extended states) and the spatial distribution of the eigenfunctions (wave function amplitude of nondegenerate states or sum of the wave function amplitudes of degenerate states) are directly reflected in the LDOS. Spatial mapping of the LDOS's shows a reduction of the lowest excitation energies in different regions of the system when the local lattice structure of the In0.25Ga0.75As layer relaxes from completely strained to completely relaxed. By comparing the calculated results with photoluminescence measurement data, we conclude that the strain in the In0.25Ga0.75As layer relaxes linearly from the heterointerface with the Al0.5Ga0.5As buffer layer to the heterointerface with the top GaAs layer.

We report the use of intermixing techniques to modify GaAs/AlGaAs multiple quantum wells (MQWs). A large shift in the response wavelength of the GaAs/AlGaAs MQW-based infrared photodetector is obtained by proton implantation and then a standard annealing