Related papers: Valence instability across magnetostructural trans…
High pressure x-ray diffraction up to 30 GPa and resonant emission x-ray spectroscopy and partial fluorescence yield x-ray absorption spectroscopy up to 52 GPa were used to study how the structural and electronic properties of UTe$_2$…
The link between the metamagnetic transition and novel spin-triplet superconductivity of UTe$_2$ was discussed thermodynamically through magnetostriction measurements in a pulsed-magnetic field. We revealed a discontinuous magnetostriction…
Using a magnetocapacitance technique, we determine the magnetic field of the spin transition, B*, at filling factor nu=2/3 in the 2D electron system in GaAs/AlGaAs heterojunctions. The field B* is found to decrease appreciably as the wave…
We report Resonant inelastic x-ray scattering measurements (RIXS) in YbCu$_2$Si$_2$ at the Yb L$_{3}$ edge under high pressure (up to 22 GPa) and at low temperatures (down to 7 K) with emphasis on the vicinity of the transition to a…
Motivated by pressure experiments on FeAs-122 superconductors, we propose a scenario based on local-moment physics to explain the simultaneous disappearance of magnetism, reduction of the unit cell volume, and decrease in resistivity. In…
We predict an unconventional magnetic ground state in A$_y$Fe$_{1.6}$Se$_2$ with $\sqrt{5}\times\sqrt{5}$ Fe-vacancy superstructure under hydraulic external pressure based on first-principles simulations. While the Fe-vacancy ordering…
LuFe$_4$Ge$_2$ crystallizes in the ZrFe$_4$Si$_2$-type structure, hosting chains of Fe-tetrahedra giving rise to geometric frustration and low-dimensionality. The compound orders antiferromagnetically at around 36 K accompanied by a…
Ab initio calculations show an antiferromagnetic-ferromagnetic phase transition around 9-10 GPa and a magnetic anomaly at 12 GPa in BiFeO3. The magnetic phase transition also involves a structural and insulator-metal transition. The G-type…
Under temperature or pressure tuning, tetragonal EuPd$_2$Si$_2$ is known to undergo a valence transition from nearly divalent to nearly trivalent Eu accompanied by a volume reduction. Albeit intensive work, its microscopic origin is still…
We present a combined high-resolution x-ray diffraction and x-ray resonant magnetic scattering (XRMS) study of as-grown BaFe2As2. The structural/magnetic transitions must be described as a two-step process. At T_S = 134.5 K we observe the…
The sudden decrease in molar volume exhibited by most lanthanides under high pressure is often attributed to changes in the degree of localization of their 4f-electrons. We give evidence, based on electrical resistivity measurements of…
The structural properties of EuCo2As2 have been studied up to 35 GPa, through the use of x-ray diffraction in a diamond anvil cell at a synchrotron source. At ambient conditions, EuCo2As2 (I4/mmm) has a tetragonal lattice structure with a…
A structural orthorhombic-to-tetragonal phase transition was recently discovered in the heavy-fermion compound UTe$_2$ at a pressure $p^*\simeq3-8$~GPa [Honda \textit{et al.}, J. Phys. Soc. Jpn. \textbf{92}, 044702 (2023); Huston \textit{et…
We present results of the magnetic susceptibility on high-quality single crystals of EuPd$_2$(Si$_{1-x}$Ge$_x$)$_2$ for Ge concentrations 0 $\leq x \leq$ 0.105 performed under varying hydrostatic (He-gas) pressure 0 $\leq p \leq$ 0.5 GPa.…
Neutron and x-ray diffraction studies show that the simultaneous first-order transition to an orthorhombic and antiferromagnetic (AFM) ordered state in BaFe2As2 splits into two transitions with Co doping. For Ba(Fe0.953Co0.047)2As2, a…
Recent experimental work shows that FePS$_3$ undergoes phase transitions from $C2/m$ ($\beta\sim107^{\circ}$) to $C2/m$ ($\beta\sim90^{\circ}$) at $6$ GPa and then to metallic $P\bar{3}1m$ at $14$ GPa, with the magnetic ordering wave vector…
The pressure-temperature phase diagram of an intermediate-valence compound YbPd was revealed via simultaneous ac-calorimetry and electrical resistivity measurements. Two successive structural phase transition temperatures, $T_1$ = 125 K and…
We present a systematic pressure study of poly- and single crystalline SrFe2As2 by electrical resistivity and X-ray diffraction measurements. SrFe2As2 exhibits a structural phase transition from a tetragonal to an orthorhombic phase at…
We measured the electrical resistivity and ac magnetic susceptibility of BaFe2As2 and SrFe2As2 single crystals under pressure using a cubic anvil apparatus. For BaFe2As2, the antiferromagnetic (AF) and structural transitions are suppressed…
The pressure dependence of a large number of phonon modes in CaFe2As2 with energies covering the full range of the phonon spectrum has been studied using inelastic x-ray and neutron scattering. The observed phonon frequency changes are in…