High temperature photoluminescence up to 100°C was demonstrated from the p-doped ten-layer InAs∕InGaAs quantum dot (QD) laser structure. 1.3μm InAs QD lasers were fabricated using pulsed anodic oxidation from this structure. High output power of 882mW and low transparency current density of 5.9A∕cm2∕QD layer were obtained. Ground state (GS) lasing could be maintained from a QD laser with short cavity length of 611μm, corresponding to the maximum modal gain of 23.1cm−1 from this laser system. GS continuous wave operation up to 100°C was also demonstrated from an InAs QD laser (50×2500μm2).

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The crystallisation of amorphous Fe 44.5 Co 44.5 Zr 7 B 4 was investigated using DSC, electrical resistivity, TEM, HRTEM, CBED and VSM. Melt-spun amorphous Fe 44.5 Co 44.5 Zr 7 B 4 crystallised by the primary crystallisation mode: the DSC results showed two exothermal peaks during heating. The electrical resistivity dropped sharply during the crystallisation event, which was consistent with DSC characterisation. From TEM, HRTEM and CBED results, primary crystallisation products which appeared to be clusters of crystals were found to be single crystal precipitates; these crystals formed in a compact dendritic morphology. Direct measurement of nucleation density and volume fraction was carried out using TEM analysis. The nucleation density was found to be high even in the absence of copper addition. The crystal growth was slow when the average size reached around 30 nm; this resulted in a stable nanocrystalline structure. The soft magnetic properties were improved after nanocrystallisation, the magnetic properties were related to the crystalline volume fraction and the Herzer model.

Nanoforest carbon nanotubes (CNTs) were synthesized by biased thermal chemical vapor deposition on cobalt-containing amorphous carbon composite films. The composite films were deposited on silicon by filtered cathodic vacuum arc using a Co-containing graphite target and then CNTs were grown at 580°C using the composite film as a catalyst layer. The nanoforest multiwalled CNTs have thin diameters between 10 and 20nm. Their tips point upwards while the rest is densely tangled. They exhibit good field emission properties with a low threshold field of 1.6V∕μm and a high current density of 2.1mA∕cm2 at 3V∕μm.

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