Velev J P, Duan Chun-Gang, Belashchenko K D, Jaswal S S, Tsymbal E Y
Department of Physics and Astronomy, Nebraska Center for Materials and Nanoscience, University of Nebraska, Lincoln, NE 68588, USA.
Phys Rev Lett. 2007 Mar 30;98(13):137201. doi: 10.1103/PhysRevLett.98.137201. Epub 2007 Mar 26.
Based on first-principles calculations, we demonstrate the impact of the electric polarization on electron transport in ferroelectric tunnel junctions (FTJs). Using a Pt/BaTiO3/Pt FTJ as a model system, we show that the polarization of the BaTiO3 barrier leads to a substantial drop in the tunneling conductance due to changes in the electronic structure driven by ferroelectric displacements. We find a sizable change in the transmission probability across the Pt/BaTiO3 interface with polarization reversal, a signature of the electroresistance effect. These results reveal exciting prospects that FTJs offer as resistive switches in nanoscale electronic devices.
基于第一性原理计算,我们证明了铁电极化对铁电隧道结(FTJ)中电子输运的影响。以Pt/BaTiO₃/Pt铁电隧道结作为模型系统,我们表明,由于铁电位移驱动的电子结构变化,BaTiO₃势垒的极化导致隧穿电导大幅下降。我们发现,随着极化反转,穿过Pt/BaTiO₃界面的传输概率发生了相当大的变化,这是电阻效应的一个特征。这些结果揭示了铁电隧道结作为纳米级电子器件中的电阻开关所具有的令人兴奋的前景。