相关论文: Structural phase transitions in double perovskite …
The halide double perovskite Cs$_2$AgBiBr$_6$ has been proposed as a potential replacement for organic halide perovskites for photovoltaic applications. Further investigation of its dielectric response, optical properties and structural…
The lead-free halide double perovskite class of materials offers a promising venue for resolving issues related to toxicity of Pb and long-term stability of the lead-containing halide perovskites. We present a first-principles study of the…
The temperature dependence of the elastic properties of antiferroelectric PbHfO3 was investigated by Brillouin scattering. The two structural phase transitions of antiferroelectric-antiferroelectric-paraelectric phases were clearly…
Single crystals of Cs2BiAgBr6 lead-free perovskite were grown by crystallization from supersaturated solution. According to characterization by XRD and EBSD methods the double perovskite single crystal are of the cubic Fm-3m symmetry with…
We report the adiabatic elastic constants of single-crystal thorium dioxide over a temperature range of 77 - 350 K. Time-domain Brillouin scattering (TDBS), an all-optical, non-contact picosecond ultrasonic technique, is used to generate…
Brillouin light scattering spectroscopy was used to probe the room-temperature elasticity of crystalline high-$T_c$ superconductor Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$. A complete set of best-estimate elastic constants was obtained using…
Vacancy-ordered double perovskites K2SnX6 (X = I, Br, Cl) attract significant research interest due to their potential application as light-absorbing materials in perovskite solar cells. However, a deep insight into their material…
Lead halide hybrid perovskites consist of an inorganic framework hosting a molecular cation located in the interstitial space. These compounds have been extensively studied as they have been identified as promising materials for…
Ba2CaMoO6 was synthesized by solid state method. The crystal structure adopts cubic Fm-3m space group at room temperature with lattice parameters of 8.378231(5) {angstroms}. Upon cooling, Ba2CaMoO6 was determined to have a structural phase…
Simple perovskite crystals undergo structural phase transitions on cooling to low temperatures, which significantly change the material properties of the crystal. In this work we rigorously characterize the temperature evolution of…
A crack free and high structural quality Sr2Nb2O7 single crystals were grown by the optical float zone method using optimized growth parameters. Laue pattern confirms single crystalline nature of the grown crystal. Temperature dependent…
Optical generation of transverse coherent phonons by femtosecond light pulses is appealing for high-speed sub-THz active control of material properties. Lead-free double perovskite semiconductors, such as Cs2AgBiBr6, attract particular…
In this work, we investigate the microscopic mechanisms of anharmonic lattice dynamics and thermal transport in lead-free halide double perovskite Cs2AgBiBr6 from first principles. We combine self-consistent phonon calculations with bubble…
With increasing temperature, ${\rm Sr}_2{\rm ScSbO}_6$ undergoes three structural phase transitions at approximately ${\rm 400K}$, ${\rm 560K}$ and ${\rm 650K}$, leading to the following sequence of phases: $P2_1/n \rightarrow I2/m…
The ultrafast dynamics of the antiferrodistortive (AFD) phase transition in perovskite SrTiO3 is monitored via time-domain Brillouin scattering. Using femtosecond optical pulses, we induce a thermally driven tetragonal-to-cubic structural…
This paper presents the phase stability, opto-electronic and thermo-electric behavior of X2AuYZ6 (X = Cs, Rb; Z = Cl/Br/I) double perovskite halides by using the DFT method. The compounds belong to the cubic arrangement and are verified by…
Lead-free halide double perovskites provide a promising solution for the long-standing issues of lead-containing halide perovskites, i.e., the toxicity of Pb and the low stability under ambient conditions and high-intensity illumination.…
Recently, direct bandgap double perovskites are becoming more popular among photovoltaic research community owing to their potential to address issues of lead (Pb) toxicity and structural instability inherent in lead halide (simple)…
Optoelectronic devices operate under continuous thermal stress that may influence both long-term stability and optical properties of the active material. It is therefore useful to know the elastic properties of the active materials. In…
Double perovskite halides are emerging as promising materials for a wide range of applications, particularly in renewable energy technologies such as solar cell devices, thereby contributing to addressing global energy demands. In this…