相关论文: Ab initio Phase Diagram of Ta2O5
Tantalum pentoxide (Ta2O5) is a wide-gap semiconductor which has important technological applications. Despite the enormous efforts from both experimental and theoretical studies, the ground state crystal structure of Ta2O5 is not yet…
There have existed for a long time a paradigm that TiO phases at ambient conditions are stable only if structural vacancies are available. Using an evolutionary algorithm, we perform an ab initio search of possible zero-temperature…
Based on particle swarm optimization (PSO) algorithm and density functional theory (DFT) calculations, we identify a stable triclinic crystal structure of Ta2O5 (named as {\gamma}1-Ta2O5) at atmospheric pressure whose unit cell contains one…
A potential orthorhombic phase of Ta$_2$O$_5$, designated as Y-Ta$_2$O$_5$, is predicted under high-pressure conditions through density functional theory (DFT) calculations combined with structural search algorithms. This phase, consisting…
We investigate using first-principles calculations the atomic structure of the orthorhombic phase of Ta$_2$O$_5$. Although this structure has been studied for decades, the correct structural model is controversial owing to the complication…
Titanium dioxide, TiO$_2$, has multiple applications in catalysis, energy conversion and memristive devices because of its electronic structure. Most of these applications utilize the naturally existing phases: rutile, anatase and brookite.…
We suggest a tetragonal $I4_1/amd$ phase ($\eta$-phase) as the ground state of $\mathrm{Ta_2O_5}$ at zero temperature, which is a high symmetry version of the triclinic $\gamma$-phase $\mathrm{Ta_2O_5}$ predicted by Yang and Kawazoe. Our…
The systems Nb$_2$O$_5$-Ta$_2$O$_5$ and Nb$_2$O$_5$-V$_2$O$_5$ were investigated using thermal analysis, X-ray powder diffraction and thermodynamic simulations. Solid solution formation is possible for both systems; furthermore, both…
Novel wide-band-gap semiconductors are needed for next-generation power electronic but there is a gap between a promising material and a functional device. Finding stable contacts is one of the major challenges, which is currently dealt…
Tantalum oxides (Ta$_2$O$_5$) are characterised by attractive physical and chemical properties, such as high dielectric constants and anti-reflection behaviour. Recently, Ta$_2$O$_5$ nanoparticles have also been proposed as possible…
Tellurium trioxide, TeO3, is the only example of a trioxide adopting at ambient conditions the VF3-type structure (a distorted variant of the cubic ReO3 structure). Here we present a combined experimental (Raman scattering) and theoretical…
Supercontinuum generation (SCG) on integrated photonic platforms is a pivotal technology for developing next-generation chip-scale systems for precision spectroscopy and metrology. While significant progress has been made with silicon (Si)…
We report on the low-energy electronic structure of Tantalum ditelluride (1$T'$-TaTe$_2$), one of the charge density wave (CDW) materials from the group V transition metal dichalcogenides using angle-resolved photoemission spectroscopy…
Building usefully coherent superconducting quantum processors depends on reducing losses in their constituent materials. Tantalum, like niobium, has proven utility as the primary superconducting layer within highly coherent qubits. But,…
Tantalum, tantalum oxide and their hetero-interfaces are of tremendous technological interest in several applications spanning electronics, thermal management, catalysis and biochemistry. For example, local oxygen stoichiometry variation in…
The phase diagram and equation of state of dense nitrogen are of interest in understanding the fundamental physics and chemistry under extreme conditions, including planetary processes, and in discovering new materials. We predict several…
We provide a first-principles description of the crystalline and oxygen-deficient Ta2O5 using refined computational methods and models. By performing calculations on a number of candidate structures, we determined the low-temperature phase…
Tantalum pentoxide (Ta2O5), as a silicon-photonic-compatible material platform, has garnered significant attention for high-performance integrated photonics due to its exceptional properties: a broad transparency window spanning from 0.28…
Titanium dioxide (TiO2) is a wide band gap semiconducting material which is promising for photocatalysis. Here we present first-principles calculations to study the pressure dependence of structural and electronic properties of two TiO2…
Superconducting qubits are a key contender for quantum computing elements, but they often face challenges like noise and decoherence from two-level systems (TLS). Tantalum (Ta) qubits are notable for their long T$_1$ coherence times nearing…