Fig. 4: FTIR and TDBS response of the STO–CTO superlattices.
From: Emergent interface vibrational structure of oxide superlattices
a, Raw (solid), fitted (dashed) and residual (dot-dashed) data for FTIR from the superlattices on an NGO substrate. The 200-nm STO and CTO thin films on NGO substrates used to fit the superlattice spectra are shown in Supplementary Figs. 13b, 15e, f. The difference curves are scaled by a factor of two for clarity. b, Phonon lifetimes (black squares) as measured via TDBS compared with the thermal conductivity (red triangles, from ref. 10) of STO–CTO superlattices with varying periodicities. The strong correlation between the two techniques conclusively demonstrates a transition in phonon scattering rates across the structural transitions elucidated with STEM/EELS. The error bars represent the standard deviation.
