Related papers: Interplay between superconductivity and magnetism …
Single crystals of the Ni-doped FeAs-based superconductor SrFe2-xNixAs2 were grown using a self-flux solution method and characterized via x-ray measurements and low temperature transport, magnetization, and specific heat studies. A doping…
75As NMR and susceptiblity were measured in a Ba(Fe1-xCox)2As2 single crystal for x=6%. Nuclear Magnetic Resonance (NMR) spectra and relaxation rates allow to show that all Fe sites experience an incommensurate magnetic ordering below…
In the superconductor LaRu$_3$Si$_2$ with the Kagome lattice of Ru, we have successfully doped the Ru with Fe and Co atoms. Contrasting behaviors of suppression to superconductivity is discovered between the Fe and the Co dopants:…
The magnetic ground state of the Eu$^{2+}$ moments in a series of Eu(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ single crystals grown from the Sn flux has been investigated in detail by neutron diffraction measurements. Combined with the results…
The iron-based superconductors represent a promising platform for high-temperature superconductivity, but the interactions underpinning their pairing present a puzzle. The EuFe$_2$As$_2$ family is unique among these materials for having…
In the novel stoichiometric iron-based material RbEuFe$_{4}$As$_{4}$ superconductivity coexists with a peculiar long-range magnetic order of Eu 4f states. Using angle-resolved photoemission spectroscopy, we reveal a complex three…
We present a comprehensive set of elastic and inelastic neutron scattering measurements on a range of Fe-doped samples of U(Ru$_{1-x}$Fe$_x$)$_2$Si$_2$ with 0.01~$\le~x~\le$~0.15. All of the samples measured exhibit long-range…
The superconducting fluctuations well inside the normal state of Fe-based superconductors were studied through measurements of the in-plane paraconductivity and magnetoconductivity in high quality BaFe(2-x)NixAs2 crystals with doping levels…
We carried out 57Fe Mossbauer measurements for FeSe and Fe1.08Te to investigate the magnetic properties. There was no sign of magnetic ordering above 4.2 K for superconducting FeSe. The magnetic sextet corresponding to antiferromagnetic…
Employing {\it state of the art} high resolution photoemission spectroscopy, we studied the temperature evolution of the electronic structure of EuFe$_2$As$_2$, an unique pnictide, where antiferromagnetism of Eu layer survives within the…
We present a detailed investigation of the electronic phase diagram of effectively charge compensated Ba1-xKx(Fe1-yCoy)2As2 with x/2 = y. Our experimental study by means of x-ray diffraction, M\"ossbauer spectroscopy, muon spin relaxation…
We have constructed a pressure$-$temperature ($P-T$) phase diagram of $P$-induced superconductivity in EuFe$_2$As$_2$ single crystals, via resistivity ($\rho$) measurements up to 3.2 GPa. As hydrostatic pressure is applied, an…
We have successfully synthesized one member of LnFeAsO (Ln stands for lanthanides) with Ln=Tb. By partial substitution of Tb$^{3+}$ by Th$^{4+}$, superconductivity with onset $T_{c}$ up to 52 K was observed. In the undoped parent compound,…
We present the magnetic and superconducting phase diagram of EuFe$_2$As$_2$ for $B \parallel c$ and $B \parallel ab$. The antiferromagnetic phase of the Eu$^{2+}$ moments is completely enclosed in the superconducting phase. The upper…
Using complementary polarized and unpolarized single-crystal neutron diffraction, we have investigated the temperature-dependent magnetic structures of Eu$_{0.5}$Ca$_{0.5}$Fe$_{2}$As$_{2}$. Upon 50 \% dilution of the Eu sites with isovalent…
The magnetism in SrFe2As2 can be suppressed by electron doping through a small substitution of Fe by Co or Ni, giving way to superconductivity. We demonstrate that a massive substitution of Fe by isovalent ruthenium similarly suppresses the…
Quantum transitions in Fe-based systems are believed to involve spin, charge and nematic fluctuations. Complex structural phase diagram in these materials often emphasizes importance of covalency in their exotic properties, which is…
Imaging local magnetic field distribution in a single crystal of superconductor CaFe1.94Co0.06As2 shows the presence of anomalous remnant magnetization within Meissner like regions of the sample. Close to the superconducting transition…
We report muon spin relaxation/rotation (uSR) measurements of single crystal Ba(Fe1-xCox)2As2 with x=0.038 and 0.047. Zero field (ZF)-uSR and Transverse field (TF)-iSR measurements of these underdoped samples find the presence of magnetism…
Single crystalline CaFe2As2 and (Ca1-xNax)Fe2As2 polycrystals (0 < x < 0.66) are synthesized and characterized using structural, magnetic, electronic transport, and heat capacity measurements. These measurements show that the…