Related papers: Vibrational anomalies in AFe$_\mathbf{2}$As$_\math…
Raman spectroscopy experiments on single crystals of CuSb2O6 and CoSb2O6 quasi-one-dimensional antiferromagnets with trirutile crystal structure were performed, with a focus on the first material. The observed Raman-active phonon modes and…
We report high magnetic field linear magnetostriction experiments on CeCoIn$_5$ single crystals. Two features are remarkable: (i) a sharp discontinuity in all the crystallographic axes associated with the upper superconducting critical…
We present the results of $^{75}$As nuclear magnetic resonance (NMR), nuclear quadrupole resonance (NQR), and resistivity measurements in KFe$_2$As$_2$ under pressure ($p$). The temperature dependence of the NMR shift, nuclear spin-lattice…
The electronic structure and physical properties of the pnictide compound families $RE$OFeAs ($RE$ = La, Ce, Pr, Nd, Sm), $A$Fe$_{2}$As$_{2}$ ($A$ = Ca, Sr, Ba, Eu), LiFeAs and FeSe are quite similar. Here, we focus on the members of the…
Inelastic neutron scattering was employed to investigate the impact of electronic nematic order on the magnetic spectra of LaFeAsO and Ba(Fe$_{0.953}$Co$_{0.047}$)$_{2}$As$_{2}$. These materials are ideal to study the paramagnetic-nematic…
We study superconducting FeSe (Tc = 9 K) exhibiting the tetragonal-orthorhombic structural transition (Ts = 90 K) without any antiferromagnetic ordering, by utilizing angle-resolved photoemission spectroscopy. In the detwinned orthorhombic…
Magnetization, resistivity and specific heat measurements were performed on the solution-grown, single crystals of six GdT$_2$Zn$_{20}$ (T = Fe, Ru, Os, Co, Rh and Ir) compounds, as well as their Y analogues. For the Gd compounds, the Fe…
The evolution of the nuclear and magnetic structures of TlFe$_{1.6}$Se$_2$ was determined in the temperature range of 5-450\,K using single crystal neutron diffraction. The Fe layers in these materials develop a corrugation in the…
High-field antiferromagnetic-resonance (AFMR) spectra were obtained in the frequency range 60 GHz < \nu < 700 GHz and for magnetic fields up to 8 T in twin-free single crystals of La_{0.95}Sr_{0.05}MnO_3. At low temperatures two…
The optical conductivity spectra of the rattling phonons in the clathrate Ba$_8$Ga$_{16}$Ge$_{30}$ are investigated in detail by use of the terahertz time-domain spectroscopy. The experiment has revealed that the lowest-lying vibrational…
We report neutron inelastic scattering measurements on the normal and superconducting states of single-crystalline Cs0.8Fe1.9Se2. Consistent with previous measurements on Rb(x)Fe(2-y)Se2, we observe two distinct spin excitation signals: (i)…
The interplay between structure, magnetism and superconductivity in single crystal Ba(Fe$_{1-x}$Co$_{x}$)$_{2}$As$_{2}$ (x=0.047) has been studied using high-resolution X-ray diffraction by monitoring charge Bragg reflections in each twin…
The optical properties of Ba$_{0.6}$K$_{0.4}$Fe$_{2}$As$_{2}$ have been determined in the normal state for a number of temperatures over a wide frequency range. Two Drude terms, representing two groups of carriers with different scattering…
We investigate the crystal structure and lattice vibrations of Sr$_2$IrO$_4$ by a combined phonon Raman scattering and x-ray powder diffraction experiment under pressures up to $66$ GPa and room temperature. Density functional theory (DFT)…
We present an experimental study of the local and collective magnetism of $\mathrm{EuFe_2As_2}$, that is isostructural with the high temperature superconductor parent compound $\mathrm{BaFe_2As_2}$. In contrast to $\mathrm{BaFe_2As_2}$,…
We report structural and physical properties of the single crystalline ${\mathrm{Ca}}{\mathrm{Mn}}_{2}{\mathrm{P}}_{2}$. The X-ray diffraction(XRD) results show that ${\mathrm{Ca}}{\mathrm{Mn}}_{2}{\mathrm{P}}_{2}$ adopts the trigonal…
While the spin dynamics of La$_{0.7}$Ca$_{0.3}$MnO$_3$ in the ferromagnetic phase are known to be unconventional, previous measurements have yielded contradictory results regarding the damping of spin wave excitations. Neutron spectroscopy…
Resistivity, specific heat and magnetic susceptibility measurements performed on SrFe2As2 samples evidence a behavior very similar to that observed in LaFeAsO and BaFe2As2 with the difference that the formation of the SDW and the lattice…
Single crystals of Cr$_2$Ge$_2$Te$_6$ were studied by high-resolution capacitance dilatometry to obtain in-plane ($B\parallel ab$) and out-of-plane ($B\parallel c$) thermal expansion and magnetostriction at temperatures between 2 and 300 K…
Parent compounds AFe2As2 (A=Ca, Ba, Eu) of the 122 family of the iron-based superconductors have been studied by 57Fe Moessbauer spectroscopy in the temperature range 4.2 K - ~300 K. Spin density waves (SDW) have been found with some…