FeSe (Tetragonal Phase)

FeSe is the structurally simplest iron-based superconductor, adopting a tetragonal PbO-type layered structure with van der Waals stacking that allows exfoliation down to a few layers. Its bulk superconducting transition is around 8 K, but Tc rises dramatically under high pressure or when a monolayer is grown on SrTiO₃ (exceeding 65 K in the monolayer). It also exhibits strongly correlated features such as electronic nematicity, making it a landmark material for studying iron-based superconductivity, nematic order, and high-Tc physics.

Sample specifications: Individual crystals measure approximately 2 mm, with a purity of up to 99.9999% (6N), and multiple high-quality single-crystal pieces included in each package.

Exfoliation: Difficult — strong interlayer bonding; mechanical exfoliation typically yields thick flakes, and ultrathin flakes are challenging to isolate.

Growth method: Flux growth.