Related papers: Magnetic measurements and 57Fe Mossbauer spectrosc…
We report on the magnetic behavior of oxygen deficient LaFeAsO1-x (x-0.10) compound, prepared by one-step synthesis, which crystallizes in the tetragonal (S.G. P4/nmm) structure at room temperature. Resistivity measurements show a strong…
57Fe-M\"ossbauer studies of superconducting Rb0.8Fe1.6Se2.0 with TC = 32.4 K were performed on single-crystalline and polycrystalline samples in the temperature range 4.2 K to 295 K. They reveal the presence of 88% magnetic and 12%…
High-pressure magnetization, structural and 57Fe M\"ossbauer studies were performed on superconducting Rb0.8Fe1.6Se2.0 with Tc = 32.4 K. The superconducting transition temperature gradually decreases on increasing pressure up to 5.0 GPa…
To probe manifestations of multiband superconductivity in oxypnictides, we measured the angular dependence of magnetic torque $\tau(\theta)$ in the mixed state of SmO$_{0.8}$F$_{0.2}$FeAs single crystals as functions of temperature $T$ and…
Detailed 57Fe Mossbauer spectroscopy measurements on superconducting NaFeAs powder samples have been performed in the temperature range 13 K < T < 300 K. The 57Fe spectra recorded in the paramagnetic range (T > TN ~ 46 K) were discussed…
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…
Superconductivity is found in 50% K-doped EuFe2As2 sample below 33 K. Our results of electrical resistivity, magnetic susceptibility and 57Fe and 151Eu Mossbauer spectroscopy provide clear evidence that the ordering of the Fe moments…
Correlation between structural/microstructural and magneto-thermal transport properties of FeAs-based SmFeAsO and SmFeAsO0.85F0.15 has been studied in detail. The Rietveld analysis of room temperature powder X-ray diffraction (XRD) data…
$^{57}$Fe M\"ossbauer spectra were measured at different temperatures between 5.9 K and 300 K on the recently discovered self-doped superconducting RbGd$_2$Fe$_4$As$_4$O$_2$ with T$_c$ as high as 35 K. Singlet pattern was observed down to…
Iron-based superconductors Ba0.7Rb0.3Fe2As2 and CaFe1.92Co0.08As2 of the '122' family have been investigated by means of the 14.41-keV Moessbauer transition in 57Fe versus temperature ranging from the room temperature till 4.2 K. A…
Static magnetic order of quasi two-dimensional FeAs compounds Sr4A2O6-xFe2As2, with A = Sc and V, has been detected by 57Fe Moessbauer and muon spin relaxation ({\mu}SR) spectroscopies. The non-superconducting stoichiometric (x = 0) A = Sc…
The LiFeP sample has been prepared by means of high-temperature solid state reaction. A transition temperature to the superconducting state was found as about 5.5 K by measurements of magnetization versus temperature. The second critical…
In this paper the magnetic behaviour of SmFeAsO and SmFeAs(O0.85F0.15) samples is presented and discussed. Molar susceptibility of SmFeAsO exhibits a local peak at T around 140K due to the establishment of a long range antiferromagnetic…
57Fe Mossbauer spectroscopy measurements were performed on a powdered CuFe2Ge2 sample that orders antiferromagnetically at ~ 175 K. Whereas a paramagnetic doublet was observed above the Neel temperature, a superposition of paramagnetic…
To probe manifestations of multiband superconductivity in oxypnictides, we measured the angular dependence of the magnetic torque $\tau(\theta)$ in the mixed state of LaO$_{0.9}$F$_{0.1}$FeAs single crystals as a function of temperature $T$…
Polycrystalline samples of a new superconducting EuAsFeO0.85F0.15 compound with critical temperature Tc=11K were prepared by solid state synthesis. Its electric and magnetic properties have been investigated in magnetic fields from 0.1 to…
The BaFe2(As1-xPx)2 compounds with x = 0 (parent), x = 0.10 (under-doped), x = 0.31, 0.33, 0.53 (superconductors with Tc = 27.3 K, 27.6 K, 13.9 K, respectively) and x = 0.70, 0.77 (over-doped) have been investigated versus temperature using…
Polycrystalline samples of underdoped (Ba1-xKx)Fe2As2 (x<=0.4) were synthesized and studied by x-ray powder diffraction, magnetic susceptibility, specific heat and 57Fe-Moessbauer-spectroscopy. The structural phase transition from…
We report specific heat measurements at magnetic fields up to 20 T on the recently discovered superconductor SmFeAsO$_{0.85}$F$_{0.15}$. The B-T diagram of a polycrystalline SmFeAsO$_{0.85}$F$_{0.15}$ sample with T$_c$ = 46 K was…
With the advent of Fe-As based superconductivity it has become important to study how superconductivity manifests itself in details of 57Fe Mossbauer spectroscopy of conventional, Fe - bearing superconductors. To this end, the iron-based…