相关论文: Band-Gap Tunability in Anharmonic Perovskite-like …
Epitaxial III-V semiconductor heterostructures are key components in modern microelectronics, electro-optics and optoelectronics. With superior semiconducting properties, halide perovskite materials are rising as promising candidates for…
The growing number of wireless communication bands has driven demand for compact, low-loss, and frequency adjustable RF filtering. Tunable acoustic resonators are well suited to address these needs, offering a path toward reconfigurable…
Tuning band gaps in two-dimensional (2D) materials is of great interest in the fundamental and practical aspects of contemporary material sciences. Recently, black phosphorus (BP) consisting of stacked layers of phosphorene was…
Surfaces and interfaces offer new possibilities for tailoring the many-body interactions that dominate the electrical and thermal properties of transition metal oxides. Here, we use the prototypical two-dimensional electron liquid (2DEL) at…
We present an $\textit{ab initio}$ study of the thermodynamic properties of cubic CaSiO$_3$ perovskite (CaPv) over the pressure and temperature range of the Earth's lower mantle. We compute the anharmonic phonon dispersions throughout the…
Magnetic measurements have been carried out in the superconducting and normal states of the optimally doped nonmagnetic bismuthate superconductor Ba0.63K0.37BiO3. The magnetic data along with previous muSR, resistivity, and tunneling data…
A thorough understanding of the temperature dependence of semiconductor band gaps is essential for optimizing optoelectronic devices. In this respect, the origin of the pronounced temperature-induced gap bowing observed in low-temperature…
Perovskite indoor photovoltaics (PIPVs) are emerging as a transformative technology for low-light intensity energy harvesting, owing to their high power conversion efficiencies (PCEs), low-cost fabrication, solution-processability, and…
The perovskite BaSnO$_3$ provides a promising platform for the realization of an earth abundant $n$-type transparent conductor. Its optical properties are dominated by a dispersive conduction band of Sn $5s$ states, and by a flatter valence…
We report a comparative study of temperature-dependent photoluminescence and structural dynamics of two perovskite semiconductors, the chalcogenide BaZrS$_3$ (BZS) and the halide CsPbBr$_3$ (CPB). These materials have similar crystal…
The electronic structure of condensed matter can be significantly affected by the electron-phonon interaction, leading to important phenomena such as electrical resistance, superconductivity or the formation of polarons. This interaction is…
Phonon polaritons in natural anisotropic crystals hold great promise for infrared nano-optics. However, the direct electrical control of these polaritons is difficult, preventing the development of active polaritonic devices. Here we…
Antiperovskites are a rich family of compounds with applications in battery cathodes, superconductors, solid-state lighting, and catalysis. Recently, a novel series of antimonide phosphide antiperovskites (A$_3$SbP, where A = Ca, Sr, Ba)…
Lead halide perovskites are causing a change of paradigm in photovoltaics. Among other peculiarities, these perovskites exhibit an atypical temperature dependence of the fundamental optical gap: It decreases in energy with decreasing…
For a class of 2D hybrid organic-inorganic perovskite semiconductors based on $\pi$-conjugated organic cations, we predict quantitatively how varying the organic and inorganic component allows control over the nature, energy and…
Transition metal perovskite chalcogenides (TMPC) are a new class of semiconductor materials with broad tunability of physical properties due to their chemical and structural flexibility. Theoretical calculations show that band gaps of TMPCs…
To address the effects of lattice anharmonicity across the perovskite to post-perovskite transition in MgSiO$_3$, we conduct calculations using the phonon quasiparticle (PHQ) approach. The PHQ is based on \textit{ab initio} molecular…
We investigate the harmonic and anharmonic contributions to the phonon spectrum of lead telluride, and perform a complete characterization of how the anharmonic effects dominate the phonons in PbTe as temperature increases. This effect is…
Lead-halide perovskites are promising materials for opto-electronic applications. Recent reports indicated that their mechanical and electronic properties are strongly affected by the lattice vibrations. Herein we report far-infrared…
We investigate the ultrafast optical response of PbTe to an intense single-cycle terahertz pulse, resonant with the soft transverse optical (TO) phonon mode of the crystal. We detect multifrequency oscillations of the reflectance…