Construction of A-B heterolayer intermetallic crystals : Case studies of the 1144-phase TM-phosphides AB(TM)(4)P-4 (TM=Fe, Ru, Co, Ni)

• The discovery of the 1144 phase, e.g., CaKFe4As4, creates opportunities to build novel intermetallics with alternative stacking of two parent compounds. Here we formalize the idea by defining a class of bulk crystalline solids with A-B stacking (including 1144 phases and beyond), which is a generalization of heterostructures from few-layer or thin-film semiconductors to bulk intermetallics. Theoretically, four families of phosphides AB(TM)(4)P-4 (TM=Fe, Ru, Co, Ni) are investigated by first-principles calculations, wherein configurational, vibrational, and electronic degrees of freedom are considered. It predicts a variety of stable 1144 phases (especially Ru- and Fe-phosphides). Stability rules are found and structural/electronic properties are discussed. Experimentally, we synthesize high-purity CaKRu4P4 as a proof of principle example. The synthetic method is simple and easily applied. Moreover, it alludes to a strategy to explore complex multicomponent compounds, facilitated by a phase diagram coordinated by collective descriptors.

Subject headings

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)