We investigate native point defects and rare-earth (co)dopants in SrAl$_2$O$_4$ using hybrid density-functional defect calculations. Europium (Eu) dysprosium (Dy) are found to be mixed valence energetically most favorable at the Sr lattice sites. However, unlike Eu where both Eu$^{2+}$ Eu$^{3+}$ can realized synthesis, Dy is stable predominantly as Dy$^{3+}$, divalent Dy$^{2+}$ may only photoge...

We investigate native point defects and rare-earth (co)dopants in SrAl$_2$O$_4$ using hybrid density-functional defect calculations. Europium (Eu) dysprosium (Dy) are found to be mixed valence energetically most favorable at the Sr lattice sites. However, unlike Eu where both Eu$^{2+}$ Eu$^{3+}$ can realized synthesis, Dy is stable predominantly as Dy$^{3+}$, divalent Dy$^{2+}$ may only photoge...

There is accumulating evidence that strontium-containing biomaterials have positive effects on bone tissue repair. We investigated the in vitro effect of a new Sr-doped bioactive glass manufactured by the sol-gel method on osteoblast viability and differentiation. Osteoblasts isolated from foetal mouse calvaria were cultured in the presence of bioactive glass particles; particles were undoped (...

We successfully synthesized La- and Sm-doped phenanthrene powder samples and observed superconductivity in them at T(c) around 6 K. The T(c)s are 6.1 K for La(1) phenanthrene and 6.0 K for Sm(1) phenanthrene, which are enhanced by about 1 and 0.5 K compared to those in A(3) phenanthrene (A = K and Rb) and in Ae(1.5) phenanthrene (Ae = Sr and Ba) superconductors, respectively. The superconductiv...

Amorphous mixed metal oxides are emerging as high performance semiconductors for thin film transistor (TFT) applications, with indium gallium zinc oxide, InGaZnO (IGZO), being one of the most widely studied and best performing systems. Here, we investigate alkaline earth (barium or strontium) doped InBa(Sr)ZnO as alternative, semiconducting channel layers and compare their performance of the el...

We have performed muon spin relaxation and low field ac-susceptibility measurements in a series of high quality samples of La 2−x Sr x CuO 4 (x = 0.08 − 0.24) as a function of temperature. Superconductivity is found to co-exist with low temperature spin glass order up to the optimally doped region where the normal state pseudogap also closes. The systematic depletion of the superfluid density w...

The Meissner effect and associated perfect 'bulk' diamagnetism together with zero resistance and gap opening are characteristic features of the superconducting state. In the pseudogap state of cuprates, unusual diamagnetic signals and anomalous proximity effects have been detected, but a Meissner effect has never been observed. Here we probe the local diamagnetic response in the normal state of...

We observe quasi-static incommensurate magnetic peaks in neutron scattering experiments on layered cobalt oxides La2-xSrxCoO4 with high Co oxidation states that have been reported to be paramagnetic. This enables us to measure the magnetic excitations in this highly hole-doped incommensurate regime and compare our results with those found in the low-doped incommensurate regime that exhibit hour...

Analyzing the motion of low–spin (s = 1/2) holes in a high–spin (S = 1) background, we derive a sort of generalized t–J Hamiltonian for the NiO2 planes of Sr–doped nickelates. In addition to the rather complex carrier–spin and spin–spin couplings we take into account the coupling of the doped holes to in–plane oxygen breathing modes by a Holstein–type interaction term. Because of strong magneti...

Rare-earth niobate and tantalate materials are of considerable interest for use as phosphors, photocatalysts and ionic conductors. We successfully synthesized Ln3MO7 (Ln = Y, Ce, Er, Ho, Tm, Yb and Lu, M = Ta, Nb) nanophosphors by a hydrothermal method using the water-soluble Lindqvist ion polyoxometalates [HNb6O19](7-) and [Ta6O19](8-) as Nb and Ta sources. The Pawley refinements of these nano...