TY - JOUR T1 - Direct measurements of optical phonons in SrTiO3 nanosystems JF - Physica E: Low-dimensional Systems and Nanostructures Y1 - 2003 A1 - Wolpert, D A1 - Korolev, K A1 - Sachs, S A1 - Knab, J A1 - Cox, W A1 - Cerne, J A1 - Markelz, A.G A1 - Zhao, T A1 - Ramesh, R A1 - Moeckly, B.H KW - Ferroelectrics KW - Finite size KW - Mode softening KW - phonons KW - Strontium titanate KW - Terahertz AB -

We use terahertz time domain spectroscopy to examine finite size effects on the optical phonon modes in SrTiO3 thin films. In temperature-dependent measurements we find a near absence of mode softening in the TO1 phonon frequency. Furthermore we see an increase in the soft mode frequency with reduced thickness. Both of these results correlate well with the reduced dielectric response observed for nanoscale ferroelectric systems.

VL - 19 SN - 1386-9477 UR - https://www.sciencedirect.com/science/article/pii/S1386947703003059 IS - 1 JO - Physica E: Low-dimensional Systems and Nanostructures ER -