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Some physical properties of BCC Fe/V and Fe/Co (0 0 1) superlattices are reviewed. The dependence of the magnetic anisotropy on the in-plane strain introduced by the lattice mismatch between Fe and V is measured and compared to a theoretical derivation. The dependence of the magnetic anisotropy (and saturation magnetisation) on the layer thickness ratio Fe/Co is measured and a value for the anisotropy of BCC Co is derived from extrapolation. The interlayer exchange coupling of Fe/V superlattices is studied as a function of the V layer thickness (constant Fe thickness) and layer thickness of Fe (constant V thickness). A region of antiferromagnetic coupling and GMR is found for V thicknesses 12-14 monolayers. However, surprisingly, a 'cutoff' of the antiferromagnetic coupling and GMR is found when the iron layer thickness exceeds about 10 monolayers.

Polarized neutron reflectivity measurements on magnetic films, containing a magnetic collinear structure, yield simple and transparent information on the direction of the magnetization. Yet the phenomenology of the neutron spin behaviour is surprisingly r, Addresses: Velthuis SGET, Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

The superiority of a local probe method over diffraction methods in determining, the interface details is demonstrated by a comparison between Fe/Co and Fe/V superlattice data. From Mossbauer spectra, the higher interface quality in the Fe/Co superlattice, Addresses: Kalska B, Univ Uppsala, Dept Phys, Box 530, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Soltan Inst Nucl Studies, PL-05400 Otwock, Poland.

Arrays of Co particles with well-defined geometry and lateral sizes in the range 0.1-0.5 mum were prepared by electron beam lithography and studied by magnetization measurements and magnetic force microscopy. The starting materials were epitaxial Co films, Addresses: Kazakova O, Chalmers Univ Technol, Dept Solid State Phys, SE-41296 Gothenburg, Sweden. Chalmers Univ Technol, Dept Solid State Phys, SE-41296 Gothenburg, Sweden. Univ Gothenburg, SE-41296 Gothenburg, Sweden. Uppsala Univ, Dept Phys, SE-75121 Up

The Fe hyperfine field distribution in Fe(xML)/V(yML) with x=5 and 10 and y=5,10 and 14 has been determined. A strong dependence in Fe magnetic field distribution as a function of thickness V as well as Fe layers has been found. (C) 2001 Elsevier Science, Addresses: Kalska B, Uppsala Univ, Dept Phys, Box 530, S-75221 Uppsala, Sweden. Uppsala Univ, Dept Phys, S-75221 Uppsala, Sweden. Soltan Inst Nucl Studies, PL-05400 Otwock, Poland.

Interfaces in Fe(xML)/V(yML) multilayers have been examined. Two pairs of samples each with definite x and y were prepared using the same deposition process and the same Elemental variations with the Fe-57 probe layers interfoliated between completed V an, Addresses: Kalska B, Univ Uppsala, Dept Phys, Box 530, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

From the Mossbauer spectrum of a high-quality Fe/Co superlattice, the interface quality was ascertained by comparison of the details of the spectrum with the published value of the magnetic hyperfine held for iron in cobalt and no detectable roughness/int, Addresses: Kalska B, Univ Uppsala, Dept Phys, Box 530, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Soltan Inst Nucl Studies, PL-05400 Otwock, Poland.

Equal amounts of Ca and Th were doped into the Nd1-2xCaxThxBa2Cu3O7-delta superconductor with 0 less than or equal to x less than or equal to 0.10. X-ray diffraction showed a single orthorhombic phase for all samples except at x = 0.10, suggesting a solubility limit below x = 0.10. For increasing doping concentration x the superconducting T-c and the electrical resistivity, rho at 275 K both vary strongly, with a linear decrease of T-c and an increase of rho. The muon spin relaxation rate, sigma, follows the Uemura line for large x, and deviates in the direction of increasing sigma-values for decreasing x. The approach of the data to the Uemura Line was compared between different alloy systems by plotting the normalized distance to the Uemura line as a function of doping concentration. Ca-Th doped samples were found to approach the Uemura line about three times faster than for Ca-Pr doping. The same replacements in Y-123 confirm this result. The strong doping concentration dependence of sigma in Ca-Th substituted samples is explained in terms of electronic disorder effects., QC 20100525

The crystal structures and giant magnetoresistance of CaF2-doped La2/3Ca1/3MnO3 compounds are investigated by means of X-ray powder diffraction (XRD) and magnetic measurements. The Rietveld powder diffraction profile fitting technique is employed to refin, Addresses: Guo YQ, Max Planck Inst Chem Phys Solid, Pirnaer Landstr 176, Gebaude 324, D-01257 Dresden, Germany. Tsing Hua Univ, Dept Mat Sci & Engn, Beijing 100084, Peoples R China. Tsing Hua Univ, State Key Lab New Ceram & Fine Proc, Beijing 100084, Peop

The fluoride La1-xSrxMnO3 compounds with a rhombohedrally distorted perovskite structure have been synthesized successfully, and their crystal structure has been investigated by means of X-ray powder diffraction. A Rietveld refinement is carried out for L, Addresses: Guo YQ, Univ Uppsala, Dept Phys, Box 530, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Univ Lund, Dept Solid Phys, S-22100 Lund, Sweden.

Positive muons implanted in proton-conducting oxides can be used to gain insight into the diffusion and trapping behaviour of light particles in these materials which are used as solid oxide electrolytes in high-temperature fuel cells. We have studied bot, Addresses: Heisel B, Univ Saarlandes, Stadtwald Geb 9-2, D-66123 Saarbrucken, Germany. Univ Saarlandes, D-66123 Saarbrucken, Germany. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

After a short introduction to mu SR with respect to the study of magnetic properties, followed by a brief outline of the principle of the high pressure-low temperature mu SR spectrometer installed at the Paul Scherrer Institute, we discuss some measuremen, Addresses: Kalvius GM, Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Uppsala Univ, Dept Phys, S-75121 Uppsala, Sweden. CNRS, Lab Louis Neel, F-38042 Grenoble, France. Univ Constance, Fac Ph

Magnetic order (including spin freezing) is absent down to similar to 15 mK in CeNiSn due to the dominance of coherent spin fluctuations caused by the Kondo interaction. Partial replacement of Ni by Cu or Pt induces a highly disordered magnetic state. The, Addresses: Kalvius GM, Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Virginia State Univ, Dept Phys, Petersburg, VA 23806 USA. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Univ Karlsru

The Mn ions occupy three different sites (8i, 8j, 8f) in equal population in YMn12, which has the tetragonal ThMn12 structure with space group I4/mmm. They possess a different magnetic moment at the 8f site (0. 14 mu(B)) compared to the 8i and 8j sites (0, Addresses: Kalvius GM, Tech Univ Munich, Dept Phys, E-15, James Franck Str, D-85747 Garching, Germany. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Virginia State Univ, Dept Phys, Petersburg, VA

The Fe hyperfine field distribution in Fe(x ML)V(y NU.) as function of x and y has been determined. The samples were prepared in a ultra-high vacuum sputtering system with Fe-57 as a probe. Low- and high-angle x-ray diffraction and Mossbauer spectroscopy, Addresses: Kalska B, Univ Uppsala, Dept Phys, Box 530, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Soltan Inst Nucl Studies, PL-05400 Otwock, Poland.

An apparatus for Mossbauer spectroscopy has been developed with a cadmium telluride (CdTe) gamma-ray detector. Complete data regarding gamma-ray energy, source velocity, temperature and real time are stored for off-line analysis. The apparatus has been us, Addresses: Bargholtz C, Univ Stockholm, Dept Phys, Box 6730, S-11385 Stockholm, Sweden. Univ Stockholm, Dept Phys, S-11385 Stockholm, Sweden. Univ Uppsala, Svedberg Lab, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

Equal amounts of Ca and Th were doped into the Nd1-2xCaxThxBa2Cu3O7-delta superconductor with 0 less than or equal to x less than or equal to 0.10. X-ray diffraction showed a single orthorhombic phase for all samples except at x = 0.10, suggesting a solub, Addresses: Rapp O, Royal Inst Technol, S-10044 Stockholm, Sweden. Royal Inst Technol, S-10044 Stockholm, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

mu SR studies in zero, longitudinal and transverse fields were carried out in the temperature range between 2 and 150 K on a polycrystalline powder sample. The data confirm the presence of two magnetic states, but each contains differently correlated spin, Addresses: Kalvius GM, Tech Univ Munich, Dept Phys, E15, James Franck Str, D-85747 Garching, Germany. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. New Mexico State Univ, Dept Phys, Las Cruces, NM 88003 USA. Virginia State Univ, Dept Phys, Peter

Muon spin rotation data on single-crystalline samples of the heavy rare earth metals Dy, Ho and Er have been obtained as function of temperature in both the antiferromagnetic (afm) and the ferromagnetic (fm) state. In the afm state the temperature depende, Addresses: Kalvius GM, Tech Univ Munich, Dept Phys, James Franck Str, D-85747 Garching, Germany. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Univ Uppsala, Inst Phys, S-75121 Uppsala, Sweden.

We have used mu SR to study NdGa6 which is a member of the REGa6 series of compounds. Below T-N (10.4 K) two precessing muon signals are observed showing that the implanted muons are trapped at two distinct sites. In the paramagnetic regime, two muon depo, Addresses: Lidstrom E, European Synchrotron Radiat Facil, BP 220, F-38043 Grenoble, France. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Tech Univ Munich, Dept Phys, D-85747 Garching, Germa

Muon-spin rotation data on single-crystalline samples of the heavy rare-earth metals Dy and Ho in their antiferromagnetic and ferromagnetic temperature regimes (20 K < T < T-N) have been obtained as function of hydrostatic external pressure up to 0.9 GPa, Addresses: Kalvius GM, Tech Univ Munich, Dept Phys, James Frank Str, D-85747 Garching, Germany. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Univ Uppsala, Inst Phys, S-75121 Uppsala, Sweden. Tech Univ Braunschweig, Inst Met Phys, D-38106 Brauns

Structural, magnetic and transport properties of the polycrystalline manganese perovskite La0.96-yNdyK0.04MnO3+delta with 0 less than or equal to y less than or equal to 0.4 have been experimentally studied. A partially disordered state is created as La i, Addresses: Mathieu R, Univ Uppsala, Dept Mat Sci, Box 534, SE-75121 Uppsala, Sweden. Univ Uppsala, Dept Mat Sci, SE-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, SE-75121 Uppsala, Sweden.

GdMn2 has a Neel transition around 100 K and a second magnetic transition near 40 K, which is considered a Curie point. The mu SR data show that both the Gd and the Mn sublattice order at T-N, in contrast to a published model. Using the signal from muons, Addresses: Kalvius GM, Tech Univ Munich, Dept Phys, James Franck Str, D-85747 Garching, Germany. Tech Univ Munich, Dept Phys, D-85747 Garching, Germany. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Virginia State Univ, Dept Phys, Petersburg, VA 23806

Significant advances have recently been made in the long-standing problem of light particle tunneling dynamics in condensed matter. This has been achieved for both charged and neutral particles: experiments using the muon spin relaxation techniques unambi, Addresses: Storchak VG, Russian Res Ctr, Kurchatov Inst, Kurchatov Sq 1, Moscow 123182, Russia. Russian Res Ctr, Kurchatov Inst, Moscow 123182, Russia. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

The magnetic properties of two-dimensional arrays of Fe particles with well-defined geometry, prepared by electron lithography from epitaxial Fe (001) films of thickness of 50 nm, have been studied. Circular particles with diameters of 0.6 and 0.4 mu m an, Addresses: Hanson M, Chalmers Univ Technol, Dept Solid State Phys, S-41296 Gothenburg, Sweden. Chalmers Univ Technol, Dept Solid State Phys, S-41296 Gothenburg, Sweden. Univ Gothenburg, S-41296 Gothenburg, Sweden. Chalmers Univ Technol, Dept Microelect &

Via ferromagnetic resonance both the magnetic anisotropy energy (MAE) and the spectroscopic splitting tensor (g tensor) for a bcc Fe-2/V-5(001) superlattice are measured independently. The theoretically proposed proportionality between the anisotropy of t, Addresses: Farle M, Free Univ Berlin, Inst Expt Phys, Arnimallee 14, D-14195 Berlin, Germany. Free Univ Berlin, Inst Expt Phys, D-14195 Berlin, Germany. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

Systematic studies with Muon Spin Rotation (mu SR) on nano-Cu and nano-Ni samples produced by pulsed electrodeposition, demonstrates that the diffusion of mu+ in nanocrystalline metals is influenced by the nanostructure. In nano-Cu the mobility of muons i, Addresses: Hartmann O, Univ Uppsala, Dept Phys, Box 530, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Univ Saarbrucken, D-66123 Saarbrucken, Germany.

Structural and magnetic properties of Fe/V(0 0 1) superlattices consisting of 3 monolayers Fe separated by V interlayers of thickness in the range 8-17 monolayers have been investigated. RHEED and X-ray diffraction investigations show that the samples are, Addresses: Nordblad P, Univ Uppsala, Dept Mat Sci, Box 534, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Mat Sci, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Linkoping Univ, Dept Phys, S-58183 Linkoping, Sweden.

The temperature-dependent magnetic anisotropies of Fe-n/V-m(001) superlattices on MgO(001) were determined by Ferromagnetic Resonance (FMR). The re-layer thickness n ranges between 2 and 4 atomic layers. The shape anisotropy dominates, and the easy-axis o, Addresses: Anisimov AN, Free Univ Berlin, Inst Phys Expt, Arnimallee 14, D-14195 Berlin, Germany. Free Univ Berlin, Inst Phys Expt, D-14195 Berlin, Germany. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

Trapping as a main feature of proton diffusion in proton conducting oxides was investigated by means of muon spin relaxation measurements, with the positive muon as tracer. In Sc-doped SrZrO3, a system with representative physicochemical properties and fa, Addresses: Hempelmann R, Univ Saarbrucken, D-66123 Saarbrucken, Germany. Univ Saarbrucken, D-66123 Saarbrucken, Germany. Uppsala Univ, Inst Phys, S-75224 Uppsala, Sweden.

Clusters of iron produced in a laser vaporization source have been characterized with time-of-flight spectra and deposited on different substrates for production of films of varying thickness. The magnetic properties of these films with thicknesses of 60, Addresses: Aklint T, Chalmers Univ Technol, Dept Phys, S-41296 Gothenburg, Sweden. Chalmers Univ Technol, Dept Phys, S-41296 Gothenburg, Sweden. Univ Gothenburg, S-41296 Gothenburg, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden.

Muon spin relaxation measurements of RE8Mg42Zn50 (RE = Gd, Tb) quasicrystals have revealed slower spin dynamics and more prompt spin freezing for Tb than Gd, due to "crystalline electric field" splitting in low rare-earth site symmetry. Inhomogeneous spin, Addresses: Noakes DR, Virginia Polytech Inst & State Univ, Dept Phys, Petersburg, VA 23806 USA. Virginia Polytech Inst & State Univ, Dept Phys, Petersburg, VA 23806 USA. Tech Univ Munich, Phys Dept E15, D-85747 Garching, Germany. Univ Uppsala, Dept Phys

Structural, magnetic, and magnetotransport properties of Fe/V (110) superlattices have been investigated. Using Al2O3 (<10(2)over bar 0>) substrates and Mo or MoxV1-x allay seed layers, the superlattices could be grown with a large in- and out-of-plane cr, Addresses: Isberg P, Univ Uppsala, Dept Phys, Box 530, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Phys, S-75121 Uppsala, Sweden. Univ Uppsala, Dept Mat Sci, S-75121 Uppsala, Sweden. Linkoping Univ, Dept Phys, S-58183 Linkoping, Sweden.

A systematic mu SR study on nano-Cu has demonstrated that the diffusion of mu(+) in nanocrystalline metals is influenced by both features of the nanostructure, i.e., by the very small grain size and by the comparatively large fraction of grain boundaries., Addresses: Soetratmo M, UNIV SAARBRUCKEN, SAARBRUCKEN, GERMANY. UNIV UPPSALA, INST FYS, UPPSALA, SWEDEN.

Using the zero-field mu SR technique, the diffusional behaviour of muons in a hydride system was investigated. The sample was made from ZrV2 that was loaded with hydrogen up to a composition of ZrV2H4.14. The results differ slightly but significantly from, Addresses: Soetratmo M, UNIV SAARLAND, D-66123 SAARBRUCKEN, GERMANY. UNIV UPPSALA, INST FYS, S-75121 UPPSALA, SWEDEN.

We resolve a long-standing puzzle for the static and dynamic critical behavior of gadolinium by a combined theoretical and experimental investigation, It is shown that the spin dynamics of a ferromagnet with hcp lattice structure and a spin-spin interacti, Addresses: Frey E, Tech Univ Munich, Inst Theoret Phys, D-85747 Garching, Germany. Tech Univ Munich, Inst Theoret Phys, D-85747 Garching, Germany. Tech Univ Munich, Inst Kernphys & Nukl Festkorperphys, D-85747 Garching, Germany. Univ Uppsala, Inst Phys, S

Muon spin rotation data on a single crystalline gadolinium sample have been obtained as function of temperature and hydrostatic external pressure up to 0.6 GPa. In the ferromagnetic state the application of pressure has a strong influence on the whole spi, Addresses: Schreier E, TECH UNIV MUNICH, DEPT PHYS, D-85747 GARCHING, GERMANY. UNIV UPPSALA, DEPT PHYS, S-75121 UPPSALA, SWEDEN.

Fe-n/V-m(001) superlattices grown on MgO(001) are studied by ferromagnetic resonance (FMR). The temperature dependence of the second- and fourth-order in- and out-of-plane magnetic anisotropies were determined from azimuthal and polar angular-dependent FM, Addresses: FREE UNIV BERLIN, INST EXPT PHYS, D-14195 BERLIN, GERMANY. UNIV UPPSALA, DEPT PHYS, S-75121 UPPSALA, SWEDEN.

We have studied the magnetic spinel (Zn)[Fe-2]O-4 (T-N approximate to 10.5 K) and the non-magnetic spinels (Zn)[Al-2]O-4, (Zn)[Ga-2]O-4, (Zn)[ZnTi]O-4 and (Zn)[ZnSn]O-4, both with surface and decay channel muons. In (Zn)[Fe-2]O-4 the relaxation rate incre, Addresses: Burghart FJ, TECH UNIV MUNCHEN WEIHENSTEPHAN, DEPT PHYS, D-85747 GARCHING, GERMANY. UNIV JENA, CHEM GEOWISSENSCH FAK, D-07743 JENA, GERMANY. TECH UNIV CAROLO WILHELMINA BRAUNSCHWEIG, INST PHYS MET, D-38106 BRAUNSCHWEIG, GERMANY. UNIV UPPSALA, D

Zero, longitudinal, and transverse field mu SR data are reported for CeRhSb and La0.1Ce0.9RhSb down to 45 mK. The muon spin relaxation at temperatures above a few Kelvin is caused by nuclear dipoles. Only at lower temperatures the additional depolarizing, Addresses: Lidstrom E, UNIV UPPSALA, DEPT PHYS, BOX 530, S-75121 UPPSALA, SWEDEN. TECH UNIV MUNICH, DEPT PHYS, D-85747 GARCHING, GERMANY. UNIV SOUTHAMPTON, DEPT PHYS, SOUTHAMPTON SO9 5NH, HANTS, ENGLAND.