Electric-field-induced soft-mode hardening in SrTiO3 films

نویسندگان

  • Akimov
  • Sirenko
  • Clark
  • Hao
  • Xi
چکیده

We have studied electric-field-induced Raman scattering in SrTiO3 thin films using an indium-tin-oxide/SrTiO3/SrRuO3 structure grown by pulsed laser deposition. The soft mode polarized along the field becomes Raman active. Experimental data for electric-field-induced hardening of the soft modes and the tuning of the static dielectric constant are in agreement described by the Lyddane-Sachs-Teller formalism. The markedly different behavior of the soft modes in thin films from that in the bulk is explained by the existence of local polar regions.

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عنوان ژورنال:
  • Physical review letters

دوره 84 20  شماره 

صفحات  -

تاریخ انتشار 2000