2D growth of high-quality magnetic CuCr2Se4 crystals with a high Curie temperature

Recently, two-dimensional (2D) magnetic materials have attracted broad attention due to their fascinating magnetic behavior and potential application in spintronics. However, most of exfoliated magnetic materials usually show random thickness and size, and the stability in the air is still a challenge. Hence, the controllable synthesis of 2D magnetic materials with good quality should be addressed. Here we report the controllable growth of 2D CuCr2Se4 crystals on mica substrates with large domain size. Most importantly, the as-grown CuCr2Se4 crystals demonstrate obvious ferromagnetic properties, showing a high Curie temperature of up to 436 K. Our discovery of 2D room-temperature ferromagnet CuCr2Se4 provides paves the way for the epitaxial growth of many more 2D magnets and provides a new platform for the spintronic applications.