Stabilizing new bismuth compounds in thin film form

Growth of unexpected phases from a composite target of BiFeO3:BiMnO3and/or BiFeO3:BiCrO3has been explored using pulsed laser deposition. The Bi2FeMnO6tetragonal phase can be grown directly on SrTiO3(STO) substrate, while two phases (S1 and S2) were found to grow on LaAlO3(LAO) substrates with narrow growth windows. However, introducing a thin CeO2buffer layer effectively broadens the growth window for the pure S1 phase, regardless of the substrate. Moreover, we discovered two new phases (X1 and X2) when growing on STO substrates using a BiFeO3:BiCrO3target. Pure X2 phase can be obtained on CeO2-buffered STO and LAO substrates. This work demonstrates that some unexpected phases can be stabilized in a thin film form by using composite perovskite BiRO3(R = Cr, Mn, Fe, Co, Ni) targets. Furthermore, it also indicates that CeO2can serve as a general template for the growth of bismuth compounds with potential room-temperature multiferroicity.