Growth, reaction and nanowire formation of Fe on the ZnS(1 0 0) surface.

The growth and reaction of Fe on a ZnS(1 0 0) substrate are studied in situ and with high lateral resolution using low energy electron microscopy (LEEM), micro low energy electron diffraction ( μLEED), x-ray photoemission electron microscopy (XPEEM), microprobe x-ray photoelectron spectroscopy ( μXPS) and x-ray magnetic circular dichroism PEEM (XMCDPEEM) for complementary structural, chemical, and magnetic characterization. Initially, a two-dimensional (Fe, Zn)S reaction layer forms with thickness that depends on growth temperature. Further growth results in the formation of a variety of three-dimensional crystals, most of them strongly elongated in the form of 'nanowires' of two distinct types, labeled as A and B.

LEEM image phase contrast of MnAs stripes.

Low energy electron microscopy (LEEM) imaging of strained MnAs layers epitaxially grown on GaAs(001) reveals striped contrast features that become more pronounced and vary systematically in width with increasing defocus, but that are completely absent in focus. Weaker subsidiary fringe-like features are observed along the stripe lengths, while asymmetric contrast reversal occurs between under-focus and over-focus conditions. A Fourier optics calculation is performed that demonstrates that these unusual observations can be attributed to a phase contrast mechanism between the hexagonal α phase and orthorhombic β phase regions of the MnAs film, which self-organize into a periodic stripe array with ridge-groove morphology.

Strain engineering of magnetic anisotropy in thin ferromagnetic films.

Magnetic properties of iron films grown on Au layers with different thicknesses on a W(110) surface are studied with spin polarized low energy electron microscopy. The iron thickness for the onset of ferromagnetic order depends approximately linearly on the thickness of underlying gold film. The easy axis direction also depends upon the Au thickness.

Pressure-induced phase transitions of piezoelectric single crystals from the langasite family: La3Nb0.5Ga5.5O14 and La3Ta0.5Ga5.5O14.

The hydrostatic compression of piezoelectric single crystals of La(3)Nb(0.5)Ga(5.5)O(14) (LNG) and La(3)Ta(0.