Structural and electronic properties of bulk YN and of the YN/ScN superlattice

First-principles prediction of the structural and electronic properties of GaxY1−xN compounds

“…These results are similar to those of Ref. [17] and our previous works using full potential linear muffintin orbitals (FPLMTO) method [18], and show a clear resemblance with the band structure of ScN [45]. For YN we have obtained an indirect fundamental gap with the top of valence band (VB) at C and the bottom of the conduction band (CB) at X.…”

“…Recently, Berkok et al [33] predicted that the possibility of two other phase transitions from cubic rock-salt (B1) structure to the orthorhombic CaSi (Cmmc) structure above 252.5 GPa and to the tetragonal AuCu (P4/mmm) structure at 303.017 GPa. Previously, we have found that the hexagonal phase named h-MgO (A3) is a metastable phase and that it is more stable than the wurtzite structure (B4) because its minimum was 0.12 eV/ unit cell (34%) lower than the minimum of B4 [18]. The finding Fig.…”

“…YN is also expected to be transformed to the CsCl (B2) phase under high pressure [17,18,39]. Recently, Berkok et al [33] predicted that the possibility of two other phase transitions from cubic rock-salt (B1) structure to the orthorhombic CaSi (Cmmc) structure above 252.5 GPa and to the tetragonal AuCu (P4/mmm) structure at 303.017 GPa.…”

“…ScN has a reasonable lattice mismatch with GaN (<2%) and therefore it has been thought to be a good replacement for InN in the combination with GaN as GaN/ScN heterostructures [14] or ScGaN alloys [15] or to combination with AlN as ScAlN alloys [16]. However, recent investigations on Yttrium Nitrides (YN) have shown that the latter has many similarities with ScN [17][18][19], and thus we find it justified to pay a particular attention to the Ga x Y 1Àx N ternary compounds.…”

Infrared dielectric functions and optical phonons of wurtzite YxAl1−xN (0 ⩽ x ⩽ 0.22)

“…YN crystallizes in the rock salt structure and is a promising transition nitride material for thermoelectric and thermionic applications. First principle studies have confirmed the semiconductor character of YN [5], however, the YN band gap is largely debated and theoretical values of 0.2 eV [6], 0.49 eV [7], 0.54 eV [8], 0.85 eV [9] and 0.97 eV [10] have been reported. Bibliographic records regarding alloying YN with group-IIIA nitrides are very scarce and mostly experimental studies on YxIn1-xN (0 ≤ x ≤ 0.094) [7] thin epitaxial films and theoretical calculations on (Sc,Y)0.5(Al,Ga,In)0.5N [2], YxAlyGa1-x-yN [11] and AlxYyB1-x-yN [12] alloys can be found.…”