相关论文: Mixed magnetic phases in (Ga,Mn)As epilayers
Mn-doped wurtzite GaN epilayers have been grown by nitrogen plasma-assisted molecular beam epitaxy. Correlated SIMS, structural and magnetic measurements show that the incorporation of Mn strongly depends on the conditions of the growth.…
Large magnetocaloric effect has been observed in Mn3O4 around its ferrimagnetic transition at TN = 42.75 K. Field-induced isothermal entropy changes (\DeltaS) were derived from both magnetic and calorimetric techniques. The maximum…
We present a mean-field theory describing the influence of long-range dipolar forces on the temperature transition from the paramagnetic to ordered phases in frustrated Heisenberg spiral magnets. It is shown that the dipolar interaction…
We examine the Mn concentration dependence of the electronic and magnetic properties of optimally annealed Ga1-xMnxAs epilayers for 1.35% < x < 8.3%. The Curie temperature (Tc), conductivity, and exchange energy increase with Mn…
Ferromagnetic shape memory alloys Ni$_{2+x}$Mn$_{1-x}$Ga were studied in the range of compositions $0.16 \le x \le 0.36$. Experimental phase diagram, constructed from differential scanning calorimetry, transport and magnetic measurements,…
This work reports on first principles calculations of the electronic and magnetic structure of tetragonal Heusler compounds with the composition Rh$_2$Fe$_{x}$Co$_{1-x}$Sb ($0\leq x\leq1$). It is found that the magnetic moments increase…
Magnetic properties of MnAs were studied as a function of temperature with a superconducting interference device (5 K to 350 K), and atomic force microscopy/magnetic force microscopy (20 K to 360 K). Structural and magnetic properties of…
The thermodynamics of layered antiferro- and ferromagnets with a weak interlayer coupling and/or easy-axis anisotropy is investigated. A crossover from an isotropic 2D-like to 3D Heisenberg (or 2D Ising) regime is discussed within the…
The zero temperature phase diagram of a one-dimensional S=2 Heisenberg ferromagnet with single-ion cubic anisotropy is studied numerically using the density-matrix renormalization group method. Evidence is found that although the model does…
Dc and ac-magnetic susceptibility ($\chi$), specific heat ($C_\mathrm{P}$), electrical resistivity ($\rho$) and magnetoresistance measurements performed on the new polycrystalline compound $\mathrm{Gd_2AgSi_3}$, crystallizing in the…
We demonstrate that the reorientation transition from out-of-plane to in-plane magnetization with decreasing temperature as observed experimentally in Ni-films on Cu(001) can be explained on a microscopic basis. Using a combination of mean…
We have performed a systematic investigation of magnetotransport of a series of as-grown and annealed Ga1-xMnxAs samples with 0.011 <= x <= 0.09. We find that the anisotropic magnetoresistance (AMR) generally decreases with increasing…
A set of thin film Mn$_x$Si$_{1-x}$ alloy samples with different manganese concentration x = 0.44 - 0.63 grown by the pulsed laser deposition (PLD) method onto the Al$_2$O$_3$(0001) substrate was investigated in the temperature range 4 -…
The magneto-crystalline anisotropy (MCA) of (Ga,Mn)As films has been studied on the basis of ab-initio electronic structure theory by performing magnetic torque calculations. An appreciable contribution to the in-plane uniaxial anisotropy…
Using dc and ac magnetometry, the pressure dependence of the magnetization of the three-dimensional antiferromagnetic coordination polymer Mn(N(CN)$_{2}$)$_{2}$ was studied up to 12 kbar and down to 8K. The magnetic transition temperature,…
Precise magnetic hysteresis measurements of small single crystals of Mn$_{12}$ acetate of spin 10 have been conducted down to 0.4 K using a high sensitivity Hall magnetometer. At higher temperature (>1.6K) step-like changes in magnetization…
Currently, aging effects occurring in multilayer systems attract much attention from researchers. In our research we looked at the behavior of multilayer systems that depend on anisotropy, magnetoresistance and susceptibility.All these…
From a systematic study of the electrical resistivity $\rho(T,H)$, magnetic susceptibility $\chi(T,H)$, isothermal magnetization $M(H)$ and the specific heat $C(T,H)$, a temperature-magnetic field ($T$-$H$) phase diagram has been…
The two dimensional electron gas (2DEG) in moderate magnetic fields in ultra-clean AlAs-GaAs heterojunctions exhibits transport anomalies suggestive of a compressible, anisotropic metallic state. Using scaling arguments and Monte Carlo…
The magnetic coupling between iron and alpha - MnAs in the epitaxial system Fe/MnAs/GaAs(001) has been studied at the sub-micron scale, using element selective x-ray photoemission electron microscopy. At room temperature, MnAs layers…