Haigh, J A, Rushforth, A W, King, C S, Edmonds, K W, Campion, R P, Foxon, C T, ...
We demonstrate a simple, low cost, magneto-transport method for rapidly characterizing the magnetic anisotropy and anisotropic magneto-resistance (AMR) of ferromagnetic devices with uniaxial magnetic...
Manipulation of the magnetic configuration of (Ga,Mn)As nanostructures (2009)
Haigh, J. A., Wang, M., Rushforth, A. W., Ahmad, E., Edmonds, K. W., Campion, R. P., ...
We have studied the magnetic reversal of L-shaped nanostructures fabricated from (Ga,Mn)As. The strain relaxation due to the lithographic patterning results in each arm having a uniaxial magnetic...
Achieving High Curie Temperature in (Ga,Mn)As (2008)
Wang, M, Campion, R P, Rushforth, A W, Edmonds, K W, Foxon, C T, Gallagher, B L
We study the effects of growth temperature, Ga:As ratio and post-growth annealing procedure on the Curie temperature, Tc, of (Ga,Mn)As layers grown by molecular beam epitaxy. We achieve the highest...
Wang, K. Y., Irvine, A. C., Campion, R. P., Foxon, C. T., Wunderlich, J., Williams, D. A., ...
We have studied current-driven domain wall motion in modified Ga_0.95Mn_0.05As Hall bar structures with perpendicular anisotropy by using spatially resolved Polar Magneto-Optical Kerr Effect...
Wang, K Y, Irvine, A C, Wunderlich, J, Edmonds, K W, Rushforth, A W, Campion, R P, ...
We investigate the anisotropy of magnetic reversal and current-driven domain wall motion in annealed Ga_0.95Mn_0.05As thin films and Hall bar devices with perpendicular magnetic anisotropy. Hall bars...
Curie point singularity in the temperature derivative of resistivity in (Ga,Mn)As (2008)
Novak, V., Olejnik, K., Wunderlich, J., Cukr, M., Vyborny, K., Rushforth, A. W., ...
We observe a singularity in the temperature derivative $d\rho/dT$ of resistivity at the Curie point of high-quality (Ga,Mn)As ferromagnetic semiconductors with $T_c$'s ranging from approximately 80...
Huge tunnelling anisotropic magnetoresistance in (Ga,Mn)As nanoconstrictions (2008)
Giddings, A. D., Makarovsky, O. N., Khalid, M. N., Yasin, S., Edmonds, K. W., Campion, R. P., ...
We report large anisotropic magnetoresistance (AMR) behaviours in single lateral (Ga,Mn)As nanoconstriction of up to 1300%, along with large multistable telegraphic switching. The nanoconstriction...
An extensive comparison of anisotropies in MBE grown (Ga,Mn)As material (2008)
Gould, C., Mark, S., Pappert, K., Dengel, G., Wenisch, J., Campion, R. P., ...
This paper reports on a detailed magnetotransport investigation of the magnetic anisotropies of (Ga,Mn)As layers produced by various sources worldwide. Using anisotropy fingerprints to identify...
De Ranieri, E., Rushforth, A. W., Vyborny, K., Rana, U., Ahmed, E., Campion, R. P., ...
It has been demonstrated that magnetocrystalline anisotropies in (Ga,Mn)As are sensitive to lattice strains as small as 10^-4 and that strain can be controlled by lattice parameter engineering during...
Edmonds, K. W., Farley, N. R. S., Arenholz, E., Campion, R. P., Foxon, C. T., ...
We demonstrate sensitivity of the Mn 3d valence states to strain in the ferromagnetic semiconductors (Ga,Mn)As and (Al,Ga,Mn)As, using x-ray magnetic circular dichroism (XMCD). The spectral shape of...
Nonvolatile ferroelectric control of ferromagnetism in (Ga,Mn)As (2008)
Stolichnov, I., Riester, S. W. E., Trodahl, H. J., Setter, N., Rushforth, A. W., Edmonds, K. W., ...
There is currently much interest in materials and structures that provide coupled ferroelectric and ferromagnetic responses, with a long-term goal of developing new memories and spintronic logic...
Domain walls in (Ga,Mn)As diluted magnetic semiconductor (2008)
Sugawara, Akira, Kasai, H., Tonomura, A., Brown, P. D., Campion, R. P., Edmonds, K. W., ...
We report experimental and theoretical studies of magnetic domain walls in an in-plane magnetized (Ga,Mn)As dilute moment ferromagnetic semiconductor. Our high-resolution electron holography...
Rushforth, A. W., De Ranieri, E., Zemen, J., Wunderlich, J., Edmonds, K. W., King, C. S., ...
We demonstrate dynamic voltage control of the magnetic anisotropy of a (Ga,Mn)As device bonded to a piezoelectric transducer. The application of a uniaxial strain leads to a large reorientation of...
Valence band orbital polarization in III-V ferromagnetic semiconductors (2008)
Freeman, A. A., Edmonds, K. W., Campion, R. P., Farley, N. R. S., Rushforth, A. W., ...
The element-specific technique of x-ray magnetic circular dichroism (XMCD) is used to directly determine the magnitude and character of the valence band orbital magnetic moments in (III,Mn)As...
Non-volatile ferroelectric control of ferromagnetism in (Ga, Mn)As (2008)
Stolichnov, I., Riester, S. W. E., Trodahl, H. J., Setter, N., Rushforth, A. W., Edmonds, K. W., ...
The Origin and Control of the Sources of AMR in (Ga,Mn)As Devices (2007)
Rushforth, A. W., Výborný, K., King, C. S., Edmonds, K. W., Campion, R. P., Foxon, C. T., ...
We present details of our experimental and theoretical study of the components of the anisotropic magnetoresistance (AMR) in (Ga,Mn)As. We develop experimental methods to yield directly the...
Wunderlich, J., Irvine, A. C., Zemen, J., Holy, V., Rushforth, A. W., De Ranieri, E., ...
The large saturation magnetization in conventional dense moment ferromagnets offers flexible means of manipulating the ordered state through demagnetizing shape anisotropy fields but these dipolar...
Jungwirth, T., Sinova, Jairo, MacDonald, A. H., Gallagher, B. L., Novak, V., Edmonds, K. W., ...
We discuss the character of states near the Fermi level in Mn doped GaAs, as revealed by a survey of dc transport and optical studies over a wide range of Mn concentrations. A thermally activated...
Domain imaging and domain wall propagation in (Ga,Mn)As thin films with tensile strain (2007)
Wang, K. Y., Rushforth, A. W., Grant, V. A., Campion, R. P., Edmonds, K. W., Staddon, C. R., ...
We have performed spatially resolved Polar Magneto-Optical Kerr Effect Microscopy measurements on as-grown and annealed Ga0.95Mn0.05As thin films with tensile strain. We find that the films exhibit...
Anisotropic Magnetoresistance components in (Ga,Mn)As (2007)
Rushforth, A. W., Výborný, K., King, C. S., Edmonds, K. W., Campion, R. P., Foxon, C. T., ...
Our experimental and theoretical study of the non-crystalline and crystalline components of the anisotropic magnetoresistance (AMR) in (Ga,Mn)As is aimed at exploring the basic physical aspects of...
AMR and magnetometry studies of ultra thin GaMnAs films (2006)
Rushforth, A. W., Giddings, A. D., Edmonds, K. W., Campion, R. P., Foxon, C. T., Gallagher, B. L.
We have measured the Anisotropic Magnetoresistance (AMR) of ultra thin (5nm) Ga(0.95)Mn(0.05)As films. We find that the sign of the AMR can be positive or negative, which may depend on the direction...
Mn-doped Ga(As,P) and (Al,Ga)As ferromagnetic semiconductors (2006)
Masek, J., Kudrnovsky, J., Maca, F., Sinova, Jairo, MacDonald, A. H., Campion, R. P., ...
A remarkable progress towards functional ferromagnetic semiconductor materials for spintronics has been achieved in p-type (Ga,Mn)As. Robust hole-mediated ferromagnetism has, however, been observed...
Dilute moment n-type ferromagnetic semiconductor Li(Zn,Mn)As (2006)
Masek, J., Kudrnovsky, J., Maca, F., Gallagher, B. L., Campion, R. P., Gregory, D. H., ...
We propose to replace Ga in (Ga,Mn)As with Li and Zn as a route to high Curie temperature, carrier mediated ferromagnetism in a dilute moment n-type semiconductor. Superior material characteristics,...
Coulomb blockade anisotropic magnetoresistance: Singleelectronics meets spintronics (2006)
Wunderlich, J., Jungwirth, T., Kaestner, B., Irvine, A. C., Wang, K., Stone, N., ...
Single-electronics and spintronics are among the most intensively investigated potential complements or alternatives to CMOS electronics. Single-electronics, which is based on the discrete charge of...
Magnetic domain structure and magnetization reversal in (311)B Ga0.91Mn0.09As films (2006)
Pross, A., Bending, S. J., Wang, K. Y., Edmonds, K. W., Campion, R. P., Foxon, C. T., ...
Control of Coercivities in (Ga,Mn)As Thin Films by Small Concentrations of MnAs Nanoclusters (2005)
Wang, K. Y., Sawicki, M., Edmonds, K. W., Campion, R. P., Rushforth, A. W., Freeman, A. A., ...
We demonstrate that low concentrations of a secondary magnetic phase in (Ga,Mn)As thin films can enhance the coercivity by factors up to ~100 without significantly degrading the Curie temperature or...
Low-temperature magnetization of (Ga,Mn)As semiconductors (2005)
Jungwirth, T., Masek, J., Wang, K. Y., Edmonds, K. W., Sawicki, M., Polini, M., ...
We report on a comprehensive study of the ferromagnetic moment per Mn atom in (Ga,Mn)As ferromagnetic semiconductors. Theoretical discussion is based on microscopic calculations and on an effective...
Wang, K. Y., Edmonds, K. W., Zhao, L. X., Sawicki, M., Campion, R. P., Gallagher, B. L., ...
We report the results of a detailed study of the structural, magnetic and magnetotransport properties of as-grown and annealed Ga0.91Mn0.09As thin films grown on (311)A and (311)B GaAs substrates....
Reorientation Transition in Single-Domain (Ga,Mn)As (2005)
Wang, K-Y., Sawicki, M., Edmonds, K. W., Campion, R. P., Maat, S., Foxon, C. T., ...
We demonstrate that the interplay of in-plane biaxial and uniaxial anisotropy fields in (Ga,Mn)As results in a magnetization reorientation transition and an anisotropic AC susceptibility which is...
Anisotropic Magnetoresistance and Magnetic Anisotropy in High-quality (Ga,Mn)As Films (2005)
Wang, K. Y., Edmonds, K. W., Campion, R. P., Zhao, L. X., Foxon, C. T., Gallagher, B. L.
We have performed a systematic investigation of magnetotransport of a series of as-grown and annealed Ga1-xMnxAs samples with 0.011
Prospects of high temperature ferromagnetism in (Ga,Mn)As semiconductors (2005)
Jungwirth, T., Wang, K. Y., Masek, J., Edmonds, K. W., Konig, Jurgen, Sinova, Jairo, ...
We report on a comprehensive combined experimental and theoretical study of Curie temperature trends in (Ga,Mn)As ferromagnetic semiconductors. Broad agreement between theoretical expectations and...
Intrinsic and Extrinsic Contributions to the Lattice Parameter of GaMnAs (2005)
Zhao, L. X., Staddon, C. R., Wang, K. Y., Edmonds, K. W., Campion, R. P., Gallagher, B. L., ...
We report on measurements of the crystal structure and hole density in a series of as-grown and annealed GaMnAs samples. The measured hole densities are used to obtain the fraction of incorporated Mn...
Magnetism in (Ga,Mn)As Thin Films With TC Up To 173K (2004)
Wang, K. Y., Campion, R. P., Edmonds, K. W., Sawicki, M., Dietl, T., Foxon, C. T., ...
We have investigated the magnetic properties of (Ga,Mn)As thin films with Mn concentration between 1 and 9%. Ferromagnetic transition temperatures TC of up to 173K are observed. The results are...
In-plane uniaxial anisotropy rotations in (Ga,Mn)As thin films (2004)
Sawicki, M., Wang, K-Y., Edmonds, K. W., Campion, R. P., Staddon, C. R., Farley, N. R. S., ...
We show, by SQUID magnetometry, that in (Ga,Mn)As films the in-plane uniaxial magnetic easy axis is consistently associated with particular crystallographic directions and that it can be rotated from...
Search For Hole Mediated Ferromagnetism In Cubic (Ga,Mn)N (2004)
Sawicki, M., Dietl, T., Foxon, C. T., Novikov, S. V., Campion, R. P., Edmonds, K. W., ...
Results of magnetisation measurements on p-type zincblende-(Ga,Mn)N are reported. In addition to a small high temperature ferromagnetic signal, we detect ferromagnetic correlation among the remaining...
Large tunneling anisotropic magnetoresistance in (Ga,Mn)As nanoconstrictions (2004)
Giddings, A. D., Khalid, M. N., Wunderlich, J., Yasin, S., Campion, R. P., Edmonds, K. W., ...
We report a large tunneling anisotropic magnetoresistance (TAMR) in a thin (Ga,Mn)As epilayer with lateral nanoconstrictions. The observation establishes the generic nature of this effect, which...
Surface effects in MnL3,2x-ray absorption spectra from (Ga,Mn)As (2004)
Edmonds, K.W., Farley, N.R.S., Campion, R.P., Foxon, C.T., Gallagher, B.L., Johal, T.K., ...
We have identified a Mn-rich layer on the surface on (Ga,Mn)As thin films which significantly influences soft x-ray absorption measurements. The MnL3,2x-ray absorption spectra of the untreated films...
Influence of low temperature annealing on the micromagnetic structure of GaMnAs films (2004)
Pross, A., Bending, S., Edmonds, K., Campion, R. P., Foxon, C. T., Gallagher, B.
Magnetic domain imaging of ferromagnetic GaMnAs films (2004)
Pross, A., Bending, S., Edmonds, K., Campion, R. P., Foxon, C. T., Gallagher, B.
P-type conductivity in cubic GaMnN layers grown by molecular beam epitaxy (2003)
Novikov, S. V., Edmonds, K. W., Giddings, A. D., Wang, K. Y., Staddon, C. R., Campion, R. P., ...
Cubic (zinc-blende) Ga1-xMnxN layers were grown by plasma-assisted molecular beam epitaxy on GaAs (001) substrates. Some of the structures also contained cubic AlN buffer layers. Auger Electron...
Mn Interstitial Diffusion in (Ga,Mn)As (2003)
Edmonds, K. W., Boguslawski, P., Wang, K. Y., Campion, R. P., Farley, N. R. S., Gallagher, B. L., ...
We present a combined theoretical and experimental study of the ferromagnetic semiconductor (Ga,Mn)As which explains the remarkably large changes observed on low temperature annealing. Careful...
DC-transport properties of ferromagnetic (Ga,Mn)As semiconductors (2003)
Jungwirth, T., Sinova, Jairo, Wang, K. Y., Edmonds, K. W., Campion, R. P., Gallagher, B. L., ...
We study the dc transport properties of (Ga,Mn)As diluted magnetic semiconductors with Mn concentration varying from 1.5% to 8%. Both diagonal and Hall components of the conductivity tensor are...
Anisotropic Magnetoresistance in GaMnAs films (2002)
Wang, K. Y., Edmonds, K. W., Campion, R. P., Zhao, L. X., Neumann, A. C., Foxon, C. T., ...
The magnetoresistance in a series of Ga1-xMnxAs samples with 0.2 =< x =< 0.8 have been measured for three mutually orthogonal orientations of the external magnetic field. The anisotropy...
High Curie temperature GaMnAs obtained by resistance-monitored annealing (2002)
Edmonds, K. W., Wang, K. Y., Campion, R. P., Neumann, A. C., Farley, N. R. S., Gallagher, B. L., ...
We show that by annealing Ga1-xMnxAs thin films at temperatures significantly lower than in previous studies, and monitoring the resistivity during growth, an unprecedented high Curie temperature Tc...
Magnetoresistance and Hall Effect in the Ferromagnetic Semiconductor GaMnAs (2002)
Edmonds, K W, Campion, R P, Wang, K-Y, Neumann, A C, Gallagher, B L, Foxon, C T, ...
The resistivity, temperature, and magnetic field dependence of the anomalous Hall effect in a series of metallic Ga1-xMnxAs thin films with 0.015=
The Hall effect and hole densities in high Tc GaMnAs thin films (2002)
Edmonds, K. W., Wang, K. Y., Campion, R. P., Neumann, A. C., Foxon, C. T., Gallagher, B. L., ...
By studying the Hall effect in a series of low resistivity Ga1-xMnxAs samples, accurate values for the hole density p, Mn concentration x, and Curie temperature Tc are obtained over the range 0.015=
Misat, S., King, J.P., Campion, R.P., Czerwinka, P.S., Fuchs, D., Villegier, J.C.
Internat.Conf.on Physics and Chemistry of Molecular and Oxide Superconductors (MOS 99), Stockholm, S, July 28 - August 2, 1999
Surface effects in MnL3,2x-ray absorption spectra from (Ga,Mn)As
Edmonds, K.W., Farley, N.R.S., Campion, R.P., Foxon, C.T., Gallagher, B.L., Johal, T.K., ...
We have identified a Mn-rich layer on the surface on (Ga,Mn)As thin films which significantly influences soft x-ray absorption measurements. The MnL3,2x-ray absorption spectra of the untreated films...
Surface effects in MnL3,2x-ray absorption spectra from (Ga,Mn)As
Edmonds, K.W., Farley, N.R.S., Campion, R.P., Foxon, C.T., Gallagher, B.L., Johal, T.K., ...
We have identified a Mn-rich layer on the surface on (Ga,Mn)As thin films which significantly influences soft x-ray absorption measurements. The MnL3,2x-ray absorption spectra of the untreated films...