Monte Carlo simulations of the randomly frustrated three-dimensional Heisenberg model with a moderate fraction (20%) of antiferromagnetic bonds show evidence of two distinct ordering events. Below Tc the spins align collinearly and exhibit ferromagnetic order, while below Txy the transverse components of the spins freeze leading to a noncollinear s...
Published in Journal of Applied Physics
Uncertainties in the application of the/ sum rule to experimental spectra of V, Cr, Mn, Fe, Co, and Ni are discussed. An important contribution to these uncertainties is the possible presence of dichroism due to diffuse magnetic moments, which are known to exist in Fe, Co, and Ni.
Published in Journal of Applied Physics
We evaluate the possibility of using dichroic electron energy loss spectroscopy (DEELS) as an alternative to x‐ray magnetic circular dichroism (XMCD). It is well known that electron energy loss spectroscopy and x‐ray absorption spectroscopy are highly analogous, providing similar information. A simple semiclassical model suggests that DEELS might h...
Published in Journal of Applied Physics
We have studied Fe/TM multilayers (TM= Mo, Nb, Ru, Rh, Pd) using x-ray magnetic circular dischroism, magneto-optical Kerr effect, and x-ray diffraction. A diverse set of magnetic behaviors emerges from the analysis. We focus on the behavior which can be attributed to the existence of a physical interface between different chemical species. In parti...
Published in Journal of Applied Physics
The relationship between interlayer coupling and interlayer d-electron magnetic moments is studied using magnetometry and x-ray magnetic circular dichroism in Fe/Cr multilayers. Multilayers are simultaneously prepared with growth axes along different crystallographic orientations to determine the orientation dependence of these effects. It is found...
Published in Journal of Applied Physics
The technique of plasma enhanced chemical vapor deposition has been used to synthesize Fe nanoparticles in an amorphous boroncarbide matrix. The nanoparticles range in size from approximately 0.7 to 4.5 nm. It has been demonstrated that the size of the nanoparticles is proportional to the density of the Fe precursor (ferrocene) in the vapor. The ma...
Published in MRS Bulletin
Published in Journal of Applied Physics
We have studied the effects of rapid thermal annealing at 1300¿°C on GaN epilayers grown on AlN buffered Si(111) and on sapphire substrates. After annealing, the epilayers grown on Si display visible alterations with craterlike morphology scattered over the surface. The annealed GaN/Si layers were characterized by a range of experimental techniques...
Dilute frozen solutions of the single molecule magnet Ni$_4$ (S=4) have been studied using high frequency D-band (130 GHz) EPR. Despite the random orientation of the molecules, well defined EPR absorption peaks are observed, due to the strong variation of the splittings between the different spin-states on magnetic field. Temperature dependent stud...
Published in Journal of Applied Physics
We report the effects of thermally annealing, non-, just -, and thick continuous silver films for their potential applications in metal-enhanced fluorescence, a near-field concept which can alter the free-space absorption and emissive properties of close-proximity fluorophores (excited states). We have chosen to anneal a noncontinuous particulate f...
