Phase diagram of the layered oxide SnO: GW and electron-phonon studies

Abstract

First-principles calculations are performed to study the electronic properties and the electron-phonon interactions of the layered oxide semiconductor SnO. In addition to the high hole mobility that makes SnO a promising material in electronics, it has recently been reported that the semimetallic phase under pressure is superconducting. The superconducting Tc curve exhibits a dome-like feature under pressure and reaches the maximum of 1.4 K at p = 9.2 GPa. Both its crystal structure and the dome-like Tc curve are reminiscent of the Fe-based superconductor FeSe. Motivated by this observation, we investigate the electronic, phonon, and their interactions in SnO using first-principles schemes. GW approximation is adopted to correct the underestimated band gaps, including real and continuous band gaps in the semiconducting and semimetallic phases. The phase diagram showing the semiconductor-to-semimetal transition and the Tc curve has been successfully reproduced. Detailed analysis of the electron-phonon interactions demonstrate the importance of the out-of-plane motions of O atoms and the Sn-s lone pairs for the superconductivity to occur. Our method combining GW and e-ph calculations can be further extended to the study of other materials that undergo insulator-to-superconductor phase transition.

Stability and electronic properties of hybrid SnO bilayers: SnO/graphene and SnO/BN

“…To test the reliability of our modeling elements, we first performed calculations on the bulk SnO. The calculated structural parameters for the bulk SnO agree very well with the corresponding experimental [19,26] and the previously reported theoretical studies [12,[27][28][29][30][31] (table S1). For example, the calculated lattice constants, a and c, are 3.835 Å and 4.817 Å, respectively, as compared to the corresponding experimental values 3.801 Å and 4.835 Å for the bulk SnO.…”

Niobium, Tantalum, and Tungsten Doped Tin Dioxides as Potential Support Materials for Fuel Cell Catalyst Applications

“…Black SnO is a semiconductor with a direct bandgap of 2.88 eV and an indirect gap of ARTICLE 0.72 eV. [27] The crystal structure of SnO [28] is depicted in Figure 7. The oxygen coordination is highly anisotropic with 4 short and 4 longer interatomic Sn-O distances forming a square prism as coordination polyhedron with the Sn ion significantly deflected from the prism center.…”

Adsorption-controlled growth and properties of epitaxial SnO films

“…* amei2@illinois.edu Of all compounds involving Sn 2+ , stannous oxide (SnO), with its simple binary structure, represents a quintessential model system to investigate and demonstrate valence stabilization in high-quality single-crystalline form. SnO is fundamentally important for its pressure-induced insulator-metal phase transition [11], which concomitantly kindles superconductivity [11,12] as observed in isostructural FeSe [13,14] and is technologically relevant for next-generation computing [15][16][17][18] and energy-sustainable applications [19,20]. Despite its simple structure and unique properties, the quality of SnO films reported in the literature varies greatly [15,[21][22][23][24][25][26][27].…”