Nanowalls, a new nanostructural morphology of carbon, grow instead of nanotubes under microwave plasma‐enhanced CVD conditions on substrates electrically disconnected from the lower electrode. While not fully understood, the formation of nanowalls (see Figure for top view) appears to depend on the local electric field. Due to their large surface, nanotubes may find applications in field emission displays and energy storage devices.

A light spot that is smaller than a half wavelength will subsequently diverge in all directions. In this letter, the authors model a subwavelength (0.42λ) super-resolution light beam which propagates over a long distance without any divergence. This can be achieved by placing a multibelt pure-phase-type binary optical element on the lens pupil. The authors also report a useful approach for designing the optical element, based on vector diffraction theory, which can be used in paraxial and nonparaxial focusing and imaging systems.

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Different definitions of spot size and depth of focus in optical data storage systems are analyzed and compared numerically. It appears that the differences between the definitions become more significant as the numerical aperture of the optical system increases. The relationship between spherical aberration and axial intensity is studied, and a general definition of the depth of focus based on this analysis is proposed.

The `cooling effect' of air flow is non-negligible in an ultralow-flying-height (FH) head-disk system. In this study, we develop a heat transfer model to study the heat flux and heat transfer in a head-disk interface. Moreover, a three-dimensional (3-D) finite element (FE) model is developed for steady-state analysis of a slider's thermal protrusion due to a DC write current. Results show that the heat flux is significantly different throughout a slider's air bearing surface (ABS). The high-speed air flow reduces approximately 80% of the temperature rise induced by the write current. This suggests that the actual heat flux distribution and a slider's ABS should be introduced in the thermal-structure FE analysis of a nanometer-spaced head-disk system.

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Super-resolution near-field phase change optical disks with a new mask layer of Sb70Te30 were studied. Disks with two different structures were analyzed using optical and thermal simulation methods. The simulation results showed that the optical disk exhibited maximum response when nearly half the laser spot was covered by the mask. The fast response depended on optimizing both the disk structure and reading power to match a certain speed because the effect of super-resolution near-field structure (super-RENS) was related to the position between the laser beam and the hole formed in the mask layer. Experimental results showed that the disk with a thermal shield layer, which was inserted into the dielectric layer located between the mask layer and the phase change layer, demonstrated a better thermal stability than the disk without the thermal shield layer. This is in good agreement with simulation results. Recording marks as small as 62 nm were observed.

The effects of different types of nano-oxides on the properties of spin valves have been studied. The nano-oxides that have been investigated in this study include NiFe–O, Al–O, CoFe–O, Ta–O, and Cu–O. From the point of view of overall properties (magnetoresistance ratio, change of sheet resistance, exchange coupling field, and interlayer coupling field), CoFe–O turned out to be the most desirable oxide when being used as the bottom oxide for top spin valves. As a capping layer for bottom spin valves, however, it was found that Al–O is the best choice among those investigated. Under optimum conditions, IrMn-based dual spin valves with a magnetoresistance ratio up to 21.8% has been successfully fabricated by incorporating oxide layers in both pinned ferromagnetic layers.