Raman spectroscopy of highly aligned thin films of Sr2FeMoO6

We report a comparative study of polarization‐resolved Raman spectra of highly aligned thin films of Sr1.9A0.1FeMoO6 (A = Sr, Ca, Ba) and undoped bulk polycrystalline Sr2FeMoO6 at room temperature. The films were fabricated by a non‐vacuum chemical deposition technique on LaAlO3 substrates. A site group analysis was performed to establish that there are five Ag and seven Bg modes, most of which have been identified, and six Eg modes, although the latter are not accessible in the c‐axis aligned films. One Bg mode shows clear evidence of an asymmetric lineshape, which is discussed in terms of an interaction between phonons and electronic excitations.