Related papers: New, Lead Free, Perovskites With a Diffuse Phase T…
We develop a theory to study the characteristics of dipolar / strain fluctuations in perovskite relaxors. In addition to the soft TO and TA phonons, we take into account another freedom of motion associated with the random hopping of…
We investigated the behavior of lead titanate (PbTiO3) up to 100 GPa, both at room temperature and upon laser heating, using synchrotron X ray diffraction combined with density functional theory (DFT) computations. At the high pressure…
The octahedral tilting and ferroelectric-like structural transition of LiOsO3 metallic perovskite [Nature Materials 12, 1024 (2013)] was examined using first-principles density-functional theory. In LiOsO3, a-a-a- octahedral titling mode is…
We present a systematic investigation of the role and importance of excitonic effects on the optical properties of transitions metal oxide perovskites. A representative set of fourteen compounds has been selected, including 3$d$ (SrTiO$_3$,…
Transition-metal oxides with an ABO$_3$ perovskite structure exhibit strongly entangled structural and electronic degrees of freedom and thus, one expects to unveil exotic phases and properties by acting on the lattice through various…
One-dimensional organo-metal halide Perovskite (CH3NH3PbI3) nanorods whose diameter and length are dictated by the inner size of porous silicon nanotube templates have been grown, characterized and compared to bulk perovskites in the form…
Substitutions of the zirconium and tin ions along with the indium-niobium and iron-niobium complexes for titanium in the barium modified NBT solid solutions impact the formation of phases in the process of the solid state synthesis and the…
A defect model involving cation and anion vacancies and anti-site defects is proposed that accounts for the non-stoichiometry of multi-valent $A$-site Na$_{0.5}$Bi$_{0.5}$TiO$_3$ based perovskite oxides with $ABO_3$ composition. A series of…
The oxygen-exchange behavior has been studied in half-doped manganese and cobalt perovskite oxides. We have found that the oxygen diffusivity in Gd_{0.5}Ba_{0.5}MnO_{3-\delta} can be enhanced by orders of magnitude by inducing…
The chemical ordering, electrical, optical, and magnetic properties of $Na_{0.5}Bi_{0.5}TiO_{3}$ (NBT) and 25$\%$ dysprosium doped NBT (DyNBT) were investigated in the framework of first-principles calculations using the full potential…
Halide perovskite and elpasolite semiconductors are extensively studied for optoelectronic applications due to their excellent performance together with significant chemical and structural flexibility. However, there is still limited…
State-of-the-art hybrid perovskites have demonstrated excellent functionality in photovoltaics and light-emitting applications, and have emerged as a promising candidate for exciton-polariton (polariton) optoelectronics. In the strong…
Precipitation patterns emerging in a 2D moving front are investigated on the example of NaOH diffusing into a gel containing AlCl_3. The time evolution of the precipitate Al(OH)_3 can be observed since the precipitate redissolves in the…
Neutron diffraction studies using powder samples have been used to understand the complex sequence of low temperature phase transitions of NaNbO3 in the temperature range from 12 K-350 K. Detailed Rietveld analysis of the diffraction data…
The soft modes associated with continuous-order phase transitions are associated with strong anharmonicity. This leads to the overdamped limit where the phonon quasi-particle picture can breakdown. However, this limit is commonly restricted…
While BiFeO3-based solid solutions show great promise for applications in energy conversion and storage, realizing this promise necessitates understanding the structure-property relationship in particular pertaining to the relaxor-like…
The structural characteristics of the perovskite- based ferroelectric Pb(Zn1/3Nb2/3)O3-9%PbTiO3 at the morphotropic phase boundary (MPB) region (x≃0.09) have been analyzed. The analysis is based on the symmetry adapted free energy…
We have utilized neutron powder diffraction to probe the crystal structure of layered Na$_{x}$CoO$_{2}$ near the half doping composition of $x=$0.46 over the temperature range of 2 to 600K. Our measurements show evidence of a dynamic…
The specific heats of three samples of Na0.35CoO2,1.3H2O show an evolution of the superconductivity, and its ultimate disappearance, with increasing sample age. An overall increase in pair-breaking action, which occurs preferentially in an…
The symmetry was examined using neutron diffraction method on Pb(Zn1/3Nb2/3)O3 -9%PbTiO3 (PZN/9PT) which has a composition at the morphotropic phase boundary (MPB) between Pb(Zn1/3Nb2/3)O3 and PbTiO3. The results were compared with those of…