Related papers: Theory of Curie temperature enhancement in electro…
The effect of modulation doping by Be on the ferromagnetic properties of Ga(1-x)Mn(x)As is investigated in Ga(1-x)Mn(x)As/Ga(1-y)Al(y)As heterojunctions and quantum wells. Introducing Be acceptors into the Ga(1-y)Al(y)As barriers leads to…
We have investigated the effect of Cd substitution on the archetypal heavy fermion antiferromagnet CeIn$_3$ via magnetic susceptibility, specific heat and resistivity measurements. The suppression of the Neel temperature, T$_{N}$, with Cd…
We show for the system La1-xCexCoO3 (0.1 <= x <= 0.4) that it is possible to synthesize electron-doped cobaltites by the growth of epitaxial thin films. For La1-xCexCoO3, ferromagnetic order is observed within the entire doping range (with…
High quality thin films of the ferromagnetic semiconductor EuO have been prepared and were studied using a new form of spin-resolved spectroscopy. We observed large changes in the electronic structure across the Curie and metal-insulator…
Carrier-independent ferromagnetism of chromium doped topological insulator $Bi_xSb_{2-x}Te_3$ thin films,which cannot be explained by current theory of dilute magnetic semiconductor, has been reported recently. To study if it is related to…
The superconducting properties of LaFeAsO$_{1-x}$F$_{x}$ in conditions of optimal electron-doping are investigated upon the application of external pressure up to $\sim 23$ kbar. Measurements of muon-spin spectroscopy and dc magnetometry…
Mn_5Ge_3C_x films with x>0.5 were experimentally shown to exhibit a strongly enhanced Curie temperature T_C compared to Mn_5Ge_3. In this letter we present the results of our first principles calculations within Green's function approach,…
Earlier theoretical results on $p$-$d$ and $d$-$d$ exchange interactions for zinc-blende semiconductors with $\mathrm{Cr}^{2{+}}$ and $\mathrm{Mn}^{3{+}}$ ions are revisited and extended by including contributions beyond the dominating…
We report study of magnetization, resistivity, magnetoresistance and specific heat of the pyrochlore Iridate (Eu1-xNdx)2Ir2O7 with x=0.0, 0.5 and 1.0, where spin orbit coupling, electronic correlation, magnetic frustration and Kondo…
It has been observed that impurity doping and/or ion-beam-induced damage in high $T_{c}$ superconductors cause a metal-insulator transition and thereby suppress the critical temperature. Based on our recent theory of the weak localization…
We propose to raise the critical temperature $T_c$ for superconductivity in doped C$_{60}$ molecular crystals by increasing the electronic density of states at the Fermi level $N(E_F)$ and thus the electron-phonon coupling constant in…
Ferromagnetic systems described by the double exchange model are investigated. At temperatures close to the Curie temperature, and for a wide range of doping levels, the system is unstable toward phase separation. The chemical potential…
In the framework of the diagrammatic method with self-consistent field, the maximum on the temperature dependence of the susceptibility of a weakly doped narrow-band Hubbard magnet below the Curie temperature $T_{\rm C}$ is predicted. By…
In superconducting ferromagnets for which the Curie temperature $T_{m}$ exceeds the superconducting transition temperature $T_{c}$, it was suggested that ferromagnetic spin fluctuations could lead to superconductivity with p-wave spin…
We present the calculations of the Curie temperature and magnetization of doped EuO both in the absence and in the presence of external magnetic field. The calculations were performed both for the free electrons model and for the model with…
We have investigated the thermal, transport and magnetic properties of URh$_{1-x}$Ru$_x$Ge alloys near the critical concentration $x_{cr} = 0.38$ for the suppression of ferromagnetic order. The Curie temperature vanishes linearly with $x$…
The infinite-dimensional Hubbard model is studied by means of a modified perturbation theory. The approach reduces to the iterative perturbation theory for weak coupling. It is exact in the atomic limit and correctly reproduces the…
To reflect the asymptotic freedom in the thermal direction, a temperature-dependent coupling was proposed in the literature. We investigate its effect on QCD matter with and without strong magnetic fields. Compared with the fixed coupling…
We have studied the temperature dependence of the photoemission spectra of Pr$_{1-x}$Ca$_x$MnO$_3$ (PCMO) with $x=0.25$, 0.3 and 0.5. For $x=0.3$ and 0.5, we observed a gap in the low-temperature CE-type charge-ordered (CO) phase and a…
The physical systems with ferromagnetism and "bad" metallicity hosting unusual transport properties are playgrounds of novel quantum phenomena. Recently EuTi$_{1-x}$Nb$_x$O$_3$ emerged as a ferromagnetic system where non-trivial temperature…