相关论文: Anisotropic charge dynamics in the quantum spin-li…
We have measured and analyzed the dielectric constant of the dimer Mott insulator $\kappa-$(BEDT-TTF)$_2$Cu$_2$(CN)$_3$, which is known as a playground for a spin-liquid state. Most unexpectedly, this particular organic salt has nontrivial…
We have investigated the dielectric response in an antiferromagnetic dimer-Mott insulator beta'-(BEDT-TTF)2ICl2 with square lattice, compared to a spin liquid candidate kappa-(BEDT-TTF)2Cu2(CN)3. Temperature dependence of the dielectric…
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…
We report on the anisotropic response, the charge and lattice dynamics of normal and charge-ordered phases with horizontal stripes in single crystals of the organic conductor alpha-(BEDT-TTF)2I3 determined by dc resistivity, dielectric and…
The Mott insulator $\kappa$-(BEDT-TTF)$_2$Ag$_2$(CN)$_3$ forms a highly-frustrated triangular lattice of $S=1/2$ dimers with a possible quantum-spin-liquid state. Our experimental and numerical studies reveal the emergence of a slight…
Inelastic neutron scattering measurements on the molecular dimer-Mott insulator $\kappa$-(BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Cl reveal a phonon anomaly in a wide temperature range. Starting from $T_{\rm ins}\sim50$-$60$ K where the charge gap…
A family of molecular Mott insulators on triangular lattice provided a few S=1/2 triangular quantum spin liquid candidates, with $\kappa$-(BEDT-TTF)$_2$Cu$_2$(CN)$_3$ being the most studied material of this group. The large number…
Utilizing infrared vibrational spectroscopy we have investigated dimerized two-dimensional organic salts in order to search for possible charge redistribution that might cause electronic dipoles and ferroelectricity: the quantum spin liquid…
The dimer Mott insulator $\kappa$-(BEDT-TTF)$_2$Cu$_2$(CN)$_3$ can be tuned into a metallic and superconducting state upon applying pressure of 1.5 kbar and more. We have performed dielectric spectroscopy measurements (7 kHz to 5 MHz) on…
The correlation-driven Mott transition is commonly characterized by a drop in resistivity across the insulator-metal phase boundary; yet, the complex permittivity provides a deeper insight into the microscopic nature. We investigate the…
The dimer Mott insulator $\kappa$-(BEDT-TTF)$_2$Cu$_2$(CN)$_3$ exhibits unusual electrodynamic properties. Numerical investigations of the electronic ground state and the molecular and lattice vibrations reveal the importance of the…
Motivated from recent experiments in kappa-(BEDT-TTF)_2Cu_2(CN)_3, dielectric and magnetic properties in a dimer-Mott insulator are studied. We derive the effective Hamiltonian where the number of electron per dimer is taken to be one.…
The spin excitations from the nonmagnetic charge-ordered insulating state of $\alpha$-(BEDT-TTF)$_2$I$_3$ at ambient pressure have been investigated by probing the static and low-frequency dynamic spin susceptibilities via site-selective…
Triangular lattice quasi-two-dimensional Mott insulators based on BEDT-TTF molecule and its analogies present a possibility to produce exotic phases by coupling charge and spin degrees of freedom. In this work we discuss magnetic properties…
The electrodynamic response of the organic spin-liquid candidate $\kappa$-(BEDT-TTF)$_2$Cu$_2$(CN)$_3$ has been measured in an extremely wide energy range ($10^{-13}$ to 2 eV) as a function of temperature (5 to 300 K). Below the Mott gap,…
We show that the anisotropy of the effective spin model for the dimer Mott insulator phase of $\kappa$-(BEDT-TTF)$_2X$ salts is dramatically different from that of the underlying tight-binding model. Intra-dimer quantum interference results…
The organic conductor $\kappa$-(BEDT-TTF)$_2$Cu$_2$(CN)$_{3}$ seems to form a quantum spin liquid, although at low temperatures unusual properties are seen in the charge, spin and lattice degrees of freedom. Here we report results of X-band…
We performed angular and temperature-dependent electron-spin-resonance measurements in the quasi-two-dimensional organic conductor $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]I. The interlayer spin-diffusion is much weaker compared to the Cl- and…
Mott insulators with strong spin-orbit coupling display a strongly anisotropic response to applied magnetic fields. This applies in particular to Kitaev materials, with $\alpha$-RuCl$_3$ and Na$_2$IrO$_3$ representing two important…
We report the temperature dependent dielectric properties and impedance spectroscopy investigation of Na$_3$Zr$_2$Si$_2$PO$_{12}$ in the frequency range of 20 Hz--2 MHz. The Rietveld refinement of x-ray diffraction pattern confirms the…