相关论文: Exchange Biasing of the Ferromagnetic Semiconducto…
We demonstrate the exchange coupling of a ferromagnetic semiconductor (Ga1-xMnxAs) with an overgrown antiferromagnet (MnO). Unlike most conventional exchange biased systems, the blocking temperature of the antiferromagnet (T_B = 48 +- 2 K)…
We demonstrate an exchange bias in (Ga,Mn)As induced by antiferromagnetic coupling to a thin overlayer of Fe. Bias fields of up to 240 Oe are observed. Using element-specific x-ray magnetic circular dichroism measurements, we distinguish a…
We discuss the annealing-dependence of exchange bias in Ga1-xMnxAs epilayers that are overgrown with Mn. Although pure Mn is a known antiferromagnet, we find that the as-grown Mn overlayer does not produce any exchange coupling with…
We report on the exchange biasing of self-assembled ferromagnetic GeMn nanocolumns by GeMn-oxide caps. The x-ray absorption spectroscopy analysis of this surface oxide shows a multiplet fine structure that is typical of the Mn2+ valence…
We describe a systematic study of the exchange coupling between a magnetically hard metallic ferromagnet (MnAs) and a magnetically soft ferromagnetic semiconductor (GaMnAs) in bilayer and trilayer heterostructures. An exchange spring model…
Exchange biased composites of ferromagnetic single-domain Ni nanoparticles embedded within large grains of MnO have been prepared by reduction of Ni$_x$Mn$_{1-x}$O$_4$ phases in flowing hydrogen. The Ni precipitates are 15-30 nm in extent,…
We report on the magnetic and the electronic properties of the prototype dilute magnetic semiconductor Ga$_{1-x}$Mn$_x$As using infrared (IR) spectroscopy. Trends in the ferromagnetic transition temperature $T_C$ with respect to the IR…
Electric field control of the exchange bias effect across ferromagnet/antiferromagnet (FM/AF) interfaces has offered exciting potentials for low-energy-dissipation spintronics. In particular, the solid state magneto-ionic means is highly…
We report magnetization and magetoresistance measurements in hybrid ferromagnetic metal/semiconductor heterostructures comprised of MnAs/(Ga,Mn)As bilayers. Our measurements show that the (metallic) MnAs and (semiconducting) (Ga,Mn)As…
Exhibiting antiferromagnetic interlayer coupling in dilute magnetic semiconductor multilayers is essential for the realisation of magnetoresistances analogous to giant magnetoresistance in metallic multilayer structures. In this work we use…
We use neutron reflectometry to investigate the interlayer exchange coupling between Ga$_{0.97}$Mn$_{0.03}$As ferromagnetic semiconductor layers separated by non-magnetic Be-doped GaAs spacers. Polarized neutron reflectivity measured below…
We employ the dynamical mean field approximation to perform a systematic study of magnetism in Ga_{1-x}Mn_xAs. Our model incorporates the effects of the strong spin-orbit coupling on the J=3/2 GaAs valence bands and of the exchange…
Exchange bias is a horizontal shift of the hysteresis loop observed for a ferromagnetic layer in contact with an antiferromagnetic layer. Since exchange bias is related to the spin structure of the antiferromagnet, for its fundamental…
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 control of the annealing conditions allows us…
Pinning magnetization in a ferromagnetic thin film is commonly realized through exchange biasing with an adjacent antiferromagnet. Field-cooling from above the N\'{e}el temperature is a reliable yet slow re-pinning method in exchange-biased…
The sign, magnitude, and range of the exchange couplings between pairs of Mn ions is determined for (Ga,Mn)N and (Ga,Mn)N:Si with x < 3%. The samples have been grown by metalorganic vapor phase epitaxy and characterized by secondary-ion…
Monte Carlo simulations of a system consisting of a ferromagnetic layer exchange coupled to a diluted antiferromagnetic layer described by a classical spin model show a strong dependence of the exchange bias on the degree of dilution in…
We studied the magnetic behavior of bilayers of multiferroic and nominally antiferromagnetic o-YMnO$_3$ (375~nm thick) and ferromagnetic La$_{0.7}$Sr$_{0.3}$MnO$_3$ and La$_{0.67}$Ca$_{0.33}$MnO$_3$ ($8 \ldots 225~$nm), in particular the…
The magneto-optical properties of the ferromagnetic semiconductor Ga$_{1-x}$Mn$_{x}$As are studied within the dynamical mean-field approximation (DMFA). A material-specific multiband $sp^{3}$ tight-binding Hamiltonian is employed for the…
A model consisting of random interacting anti-ferromagnetic (AF) grains coupled to a ferromagnetic (FM) layer is developed to study the exchange bias phenomenon. This simple model is able to describe several exchange bias behavior observed…