论文标题
在铁电隧道连接处的电子传输的见解
Insights into electron transport in a ferroelectric tunnel junction
论文作者
论文摘要
铁电隧道连接（FTJ）的成功取决于隧道电气（TER）效应给出的电子隧道的不对称性。该特征主要考虑三种运输机制：直接隧穿，热发射发射和福勒 - 诺德海姆隧道。在这里，通过分析温度对TER的影响，我们表明仅考虑这些机制可能不足以充分表征FTJ设备的性能。我们使用非平衡绿色函数（NEGF）方法接近FTJ中的电子隧道，该方法能够克服影响上述三种机制的局限性。我们带来的证据表明，FTJ的性能也受温度的影响，通过共振（Gamow-siegert）状态，这些状态存在于电子传输概率中，通常位于屏障上方。尽管NEGF技术无法直接访问波函数，但我们表明，对于单带传输，可以在任何给定的能量下找到波函数，尤其是在系统中的共振能量上。
The success of a ferroelectric tunnel junction (FTJ) depends on the asymmetry of electron tunneling as given by the tunneling electroresistance (TER) effect. This characteristic is mainly assessed considering three transport mechanisms: direct tunneling, thermionic emission, and Fowler-Nordheim tunneling. Here, by analyzing the effect of temperature on TER, we show that taking into account only these mechanisms may not be enough in order to fully characterize the performance of FTJ devices. We approach the electron tunneling in FTJ with the non-equilibrium Green function (NEGF) method, which is able to overcome the limitations affecting the three mechanisms mentioned above. We bring evidence that the performance of FTJs is also affected by temperature, in a non-trivial way, via resonance (Gamow-Siegert) states, which are present in the electron transmission probability and are usually situated above the barrier. Although the NEGF technique does not provide direct access to the wavefunctions, we show that, for single-band transport, one can find the wavefunction at any given energy and in particular at resonant energies in the system.
