Superconductivity of tin selenide at pressures up to 70 GPa

Pressure-Stabilized Tin Selenide Phase with an Unexpected Stoichiometry and a Predicted Superconducting State at Low Temperatures

“…As expected, SnSe goes through a phase transition from the P nma structure through Cmcm to a higher symmetry B2 structure with increasing pressure. The high-pressure crystal structures and the corresponding phase transition pressures are in good agreements with experimental observations [6,7], indicating the reliability of our calculations. SnSe 2 has a CdI 2 -type structure with a space group of P3m1 at 0 GPa, and it transforms to the R3m space group at 5 GPa.…”

“…At high pressures above 58 GPa, SnSe was found to become a superconductor at temperatures below 4.5 K [7]. Comparing to SnSe, Sn 3 Se 4 has a much lower metallization pressure, suggesting a potential superconductive transition at lower pressures.…”

“…It was shown that laminar SnSe (B16-type structure in the P nma space group) undergoes a pressure-induced structural phase transition to the B33 structure (Cmcm space group) at about 10.5 GPa [6]. Under further compression, SnSe transforms to the B2 structure (P m3m space group) and this phase was found to exhibit a superconducting transition at low temperatures above 58 GPa [7]. SnSe 2 is also a layered semiconductor with a hexagonal CdI 2 -type crystal structure (P3m1 space group) [8].…”

Sb2Se3 under pressure

“…At ambient conditions, Sb 2 Se 3 is an insulator with a band gap of ~1 eV25. Given that (a) the high-pressure bcc phases of both Bi 2 Te 3 613 and Sb 2 Te 3 23 are metallic and superconducting and (b) the respective high-pressure CsCl-type/bcc modifications for several binary compounds are also metallic46 and even superconducting47, it is reasonable to assume that the high-pressure bcc phase of Sb 2 Se 3 will also exhibit metallic, and possibly superconducting behavior. This assumption, however, needs to be checked by appropriate high-pressure electrical transport measurements.…”

Investigations of structural and optical analysis of SeS and SeSnS2 microcrystals

“…The growth of mixed bulk crystals is of recent research interest due to their applications in detectors, emitters in the infrared spectral region [1], sensors and laser materials [2], switching and memory devices [3,4], thin film polarizers [5], superconductivity crystals [6] and thermoelectric cooling materials [7]. The group-VI chalcogenides show a wide range of interesting electronic and optical properties.…”