Ferroelectricity in ultrathin BaTiO3 films: probing the size effect by ultraviolet Raman spectroscopy.
نویسندگان
چکیده
We demonstrate the dramatic effect of film thickness on the ferroelectric phase transition temperature Tc in strained BaTiO3 films grown on SrTiO3 substrates. Using variable-temperature ultraviolet Raman spectroscopy enables measuring Tc in films as thin as 1.6 nm, and a film thickness variation from 1.6 to 10 nm leads to Tc tuning from 70 to about 925 K. Raman data are consistent with synchrotron x-ray scattering results, which indicate the presence of 180 degrees domains below Tc, and thermodynamic phase-field model calculations of Tc as a function of thickness.
منابع مشابه
Ferroelectricity in Ultrathin Strained BaTiO3 Films: Probing the Size Effect by Ultraviolet Raman Spectroscopy
We demonstrate a dramatic effect of film thickness on the ferroelectric phase transition temperature, Tc, in strained BaTiO3 films grown on SrTiO3 substrates. Using variable temperature ultraviolet Raman spectroscopy enables measuring Tc in films as thin as 1.6 nm, and film thickness variation from 1.6 to 10 nm leads to Tc tuning from 70 to about 925K. Raman data are consistent with synchrotron...
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ورودعنوان ژورنال:
- Physical review letters
دوره 103 17 شماره
صفحات -
تاریخ انتشار 2009