Related papers: Dielectric Evidence for Possible Type-II Multiferr…
Ruthenium trichloride is the subject of many recent experimental and theoretical studies. Johnson et al. infer a candidate for the magnetic structure (Cc2/m) from results gathered in an extensive set of experiments on an untwined sample of…
We report on optical measurements of the 1D Heisenberg antiferromagnet KCuF3. The crystal-field excitations of the Cu2+ ions have been observed and their temperature dependence can be understood in terms of magnetic and exchange-induced…
Magnetic and/or dielectric behaviors have been studied for YBaCuFeO5, LuBaCuFeO5 and TmBaCuFeO5, which are known as members of oxygen-defect ordered perovskite systems RBaCuFeO5 (R=lanthanides Ln and other trivalent elements) and have two…
The two-dimensional organic conductor $\alpha$-(BEDT-TTF)$_2$I$_3$ undergoes a metal-insulator transition at $T_{\rm CO}=135$ K due to electronic charge ordering. We have conducted time-resolved investigations of its electronic properties…
Hexagonal YMnO$_3$ is well known for the co-occurrence of ferroelectricity and antiferromagnetism at low temperatures. Using temperature-dependent spectroscopic ellipsometry at an $a$-plane oriented single crystal, we show how the…
Epitaxial thin films of the heavy fermion superconductor UNi2Al3 with Tc{max}=0.98K were investigated. The transition temperature Tc depends on the current direction which can be related to superconducting gaps opening at different…
Magnetism of Cu$_2$(OH)$_3$Br single crystals based on a triangular lattice is studied by means of magnetic susceptibility, pulsed-field magnetization, and specific heat measurements. There are two inequivalent Cu$^{2+}$ sites in an…
We report the results of our investigations on a polycrystalline sample of Lu$_2$Ir$_3$Si$_5$ which crystallizes in the U$_2$Co$_3$Si$_5$ type structure (Ibam). These investigations comprise powder X-ray diffraction, magnetic…
Polycrystalline CuO samples with Co doping were prepared by solid state method with flowing oxygen condition and examined their structural and multiferroic properties. Structural studies have confirmed single phase monoclinic crystal…
Measurements of the magnetic Gr\"uneisen parameter ($\Gamma_B$) and specific heat on the Kitaev material candidate $\alpha$-RuCl$_3$ are used to access in-plane field- and temperature-dependence of the entropy up to 12 T and down to 1 K. No…
Dielectric measurements at very low temperature indicate that in a glass with the eutectic composition BaO-Al$_2$O$_3$-SiO$_2$ a phase transition occurs at 5.84 mK. Below that temperature small magnetic fields of the order of 10 $\mu$T…
A pseudo honeycomb system Li2RuO3 exhibits a second-order-like transition at temperature T=Tc=540 K to a low-T nonmagnetic phase with a significant lattice distortion forming Ru-Ru pairs. For this system, we have calculated the band…
We present thermal expansion alpha, magnetostriction and specific heat C measurements of \tal, which shows a quantum phase transition from a spin-gap phase to a Neel-ordered ground state as a function of magnetic field around H_{C0}->4.8T.…
We performed factor-group analysis of all phonons in possible monoclinic C2/c and C2 structures of BiMnO3 and compared it with our experimental infrared and Raman spectra. We conclude that the crystal structure is centrosymmetric C2/c in…
The Mott insulator a-RuCl3, featuring the intertwined interplay of spin-orbit coupling (SOC) and Kitaev spin correlations, provides an unparalleled platform for probing quantum many-body physics. Using scanning tunneling…
We performed third-order electrical conductivity measurements on the organic conductor $\alpha$-(BEDT-TTF)$_2$I$_3$ using an ac bridge technique sensitive to nonlinear signals. Third-order conductance $G_3$ is clearly observed even at low…
For the past decades, the low-temperature phase of Ca$_3$Ru$_2$O$_7$ below the 48K first-order phase transition remains a puzzle with controversial suggestions involving metallic ferroelectric, orbital or magnetic ordering. Through analysis…
The Mott insulator \kappa-(BEDT-TTF)2Cu[N(CN)2]Cl consists of molecular dimers arranged on an anisotropic triangular lattice and develops a canted antiferromagnetic ground state. It has recently been suggested that this system features…
Dielectric constant measurement under magnetic field is an efficient technique to study the coupling between charges and spins in insulating materials. For magnetic oxides, the geometric frustration is known to be a key ingredient to…
We have investigated dielectric properties in Mott insulators GdMnO$_{3}$ and TbMnO$_{3}$ under magnetic fields and external quasihydrostatic pressures. In the case of GdMnO$_{3}$, thermal hysteresis for dielectric constant $\epsilon$ and…