相关论文: Origin of Low-Energy Excitations in Charge-Ordered…

THz time-domain spectroscopy was used to directly probe the low-energy (0.5--5 meV) electrodynamics of the charge-ordered manganite Pr$_{0.7}$Ca$_{0.3}$MnO$_3$. We revealed the existence of a finite peak structure around 2--3 meV well below…

Mixed valent manganites are noted for their unusual magnetic,electronic and structural phase transitions. The La1-xCaxMnO3 phase diagram shows that below transition temperatures in the range 100-260 K, compounds with 0.2 < x < 0.5 are…

We find a characteristic low-energy peak structure located in the range of 100-300 cm$^{-1}$ in the optical conductivity spectra of a quasi-two-dimensional organic compound with a triangular lattice,…

The electron in a solid can be considered a bound state of the three independent, fundamental degrees of freedom creating quasi-particles: spinons, carrying the electron spin; plasmons carrying the collective charge mode and orbitons…

In the optical conductivity of four different manganites with commensurate charge order (CO), strong peaks appear in the meV range below the ordering temperature T_{CO}. They are similar to those reported for one-dimensional charge density…

We report an infrared reflection spectroscopy study of La$_{1/2}$Ca$_{1/2}$MnO$_3$ over a broad frequency range and temperature interval which covers the transitions from the high temperature paramagnetic to ferromagnetic and, upon further…

We report an inelastic neutron scattering study of acoustic phonons in the charge and orbitally ordered bilayer manganite LaSr$_2$Mn$_2$O$_7$. For excitation energies less than $15\,\rm{meV}$, we observe an abrupt increase (decrease) of the…

We report resonant inelastic x-ray scattering experiments of the orbital ordered manganite LaMnO3. When the incident photon energy is tuned near the Mn K absorption edge, the spectra reveal three features at 2.5 eV, 8 eV and 11 eV. The 8 eV…

We investigated temperature (T)- and magnetic field-dependent optical conductivity spectra (\s\w) of a La_5/8-yPr_yCa_3/8MnO_3 (y~0.35) single crystal, showing intriguing phase coexistence at low T. At T_C < T < T_CO, a dominant…

Charge-lattice fluctuations are observed in the layered perovskite manganite LaSr2Mn2O7 by Raman spectroscopy as high as 340 K and with decreasing temperature they become static and form a charge ordered (CO) phase below TCO=210 K. In the…

Based on the Hamiltonian of small polarons with the strong nearest neighbor repulsion, we have investigated the charge ordering phenomena observed in half-doped manganites R_{1/2}A_{1/2}MnO_3. We have explored possible consequences of the…

In this work the charge transport properties of charge ordered (CO) La1-xCaxMnO3 (LCMO) (x= 0.55, 0.67) epitaxial thin films and polycrystals are discussed following the recent controversy of localised electron states vs. weakly or de-…

Magnetization, magnetoresistance, and magnetodielectric measurements have been carried out on the half doped charge ordered manganite, Pr_0.5Ca_0.5MnO_3. The low temperature state is found to be strongly dependent on the oxygen…

The dielectric behavior of half doped manganites La0.5Ca0.5-xSrxMnO3 (0.1 \leq \times \leq 0.4) with varying magnetic ground states has been studied. The real part of relative permittivity as a function of temperature {\epsilon}^'(T),…

We have studied the magnetic relaxation properties of the phase-separated manganite compound La0.250Pr0.375Ca0.375MnO3 . A series of polycrystalline samples was prepared with different sintering temperatures, resulting in a continuous…

High temperature (T) studies of La_{1-x}Ca_{x}MnO_{3} show that charge and phonon transport is significantly suppressed in a narrow doping region of x~1/2 and in a wide T range up to 900 K, which accompanies anomalous broadening of x-ray…

Infrared absorption study has been carried out on a series of half doped manganites, $La_{0.5}Ca_{0.5-x}Sr_{x}MnO_{3}$ $(0.1\leq x\leq0.5)$, with varying magnetic ground state. The charge ordering transition observed in samples with…

Low energy excitations in the multiferroic material TbMnO3 have been investigated by Raman spectroscopy. Our observations reveal the existence of two peaks at 30 cm-1 and 60 cm-1. They are observed in the cycloidal phase below the Curie…

Despite decades of intensive experimental and theoretical efforts, the physics of cuprate high-temperature superconductors in general, and, in particular, their normal state, is still under debate. Here, we report our investigation of…

In the charge-ordered phase of strongly doped manganites La$_{1-x}$Ca$_x$MnO$_3$ ($x \geq 0.5$) absorption lines appear in the terahertz spectral range for commensurate $x$ values right below the charge-ordering temperature. They are…