Crystal Growth Techniques for Layered Superconductors

Abstract

Layered superconductors are attractive because some of them show high critical temperatures. While their crystal structures are similar, these compounds are composed of many elements. Compounds with many elements tend to be incongruent melting compounds, thus, their single crystals cannot be grown via the melt-solidification process. Hence, these single crystals have to be grown below the decomposition temperature, and then the flux method, a very powerful tool for the growth of these single crystals with incongruent melting compounds, is used. This review shows the flux method for single-crystal growth technique by self-flux, chloride-based flux, and HPHT (high-pressure and high-temperature) flux method for many-layered superconductors: high-T c cuprate, Fe-based and BiS 2 -based compounds.

Monolayer WS2 electro- and photo-luminescence enhancement by TFSI treatment

“…WS 2 crystals are synthesized using a two-step self-flux technique [81] using 99.9999% purity W and S powders without any transporting agents. Commercial (Alfa Aesar) sources of powders contain a number of defects and impurities (Li, O, Na, and other metals as determined by secondary ion mass spectroscopy).…”

Flux Growth and Superconducting Properties of (Ce,Pr)OBiS2 Single Crystals

“…Flux synthesis has been utilized widely for the synthesis of solid-state materials (Oishi et al, 2004;Akira et al, 2019), especially for discovering compounds with complex structures (DiSalvo and Clarke, 1996; Bugaris and zur Loye, 2012) Nonetheless, an interesting feature of synthesis using a flux, in addition to structural determination, is to explore various properties (Yamane et al, 1997;Mizuno et al, 2014;Miura et al, 2016;Chiang et al, 2018). Superconducting materials also can be synthesized by the flux method, and the properties of the synthesized products can be controlled by the synthesis condition (Nagao, 2017). For example, we very recently found that Sm(O,F)BiS 2 single crystals synthesized by KCl-KI exhibited superconductivity (Kinami et al, 2019), in contrast to the non-superconducting Sm(O,F)BiS 2 powder and crystals synthesized using CsCl-KCl flux reported previously (Thakur et al, 2015).…”

Layered Superconductors

“…Therefore, we invited Nagao to review crystal growth technique for layered superconductors [21]. For various layered superconductors, the suitable method to grow high quality crystal is introduced.…”