Effects of electrodes and space charges on the tunneling electroresistance in the ferroelectric tunnel junction with a SrTiO3/BaTiO3 composite barrier
Effects of electrodes and space charges on the tunneling electroresistance in the ferroelectric tunnel junction with a SrTiO3/BaTiO3 composite barrier
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DOI：
10.1063/1.3457451
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发表时间：
2010-06
影响因子：
4
通讯作者：
Yin-Zhong Wu;S. Ju;Zhen-ya Li
中科院分区：
文献类型：
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作者：
Yin-Zhong Wu;S. Ju;Zhen-ya Li
利用应变纳米铁电薄膜的晶格模型和量子隧穿理论，从理论上研究了具有SrTiO_3/BaTiO_3复合势垒的铁电隧道结(FTJ)的隧穿电阻(TER)。根据第一性原理计算了复合势垒内局部极化的精确分布。结果表明，随着钛酸锶阻挡层厚度的增加，TER敏感地依赖于电极的选择。利用应变纳米铁电薄膜的晶格模型和量子隧道理论，对具有SrTiO3/BaTiO3复合势垒的铁电隧道结(FTJ)的隧道电阻(TER)进行了理论研究。根据第一性原理计算了复合势垒内局部极化的精确分布。结果表明，随着钛酸锶阻挡层厚度的增加，TER敏感地依赖于电极的选择。存在于两个势垒交界处的空间电荷将增强TER，并提供在FTJ中实现大TER的有效途径。
Using the lattice model for strained nanoscale ferroelectric films and quantum tunneling theory, we present a theoretical investigation of tunneling electroresistance (TER) in the ferroelectric tunnel junction (FTJ) with a SrTiO3/BaTiO3 composite barrier. The exact profile of local polarizations within the composite barrier is calculated from first principles. It is found that the TER will sensitively depend on the choice of electrode with the increase in SrTiO3 barrier’s thickness. The space charges, which exist at the interface between the two barriers, will enhance the TER, and provide an effective approach to achieving large TER in FTJs.Using the lattice model for strained nanoscale ferroelectric films and quantum tunneling theory, we present a theoretical investigation of tunneling electroresistance (TER) in the ferroelectric tunnel junction (FTJ) with a SrTiO3/BaTiO3 composite barrier. The exact profile of local polarizations within the composite barrier is calculated from first principles. It is found that the TER will sensitively depend on the choice of electrode with the increase in SrTiO3 barrier’s thickness. The space charges, which exist at the interface between the two barriers, will enhance the TER, and provide an effective approach to achieving large TER in FTJs.