纳米系统中的精确偏振估计
Toward accurate polarization estimation in nanoscopic systems
摘要：
铁电薄膜的纳米级表征是其器件应用的关键。标准的表征技术是基于检测由铁电体中的极化反转引起的纳米级电荷补偿电流（开关电流）。由于各种表面和体积限制机制，泄漏电流通常会出现在这样的测量过程中，这是经常减去使用器件的I-V特性，通过采用正-上-负-下（PUND）测量方案。通过对常用的铁电体BiFeO 3进行纳米级开关电流测量，我们发现这种表征方法可能容易在铁电样品的极化估计中出现较大的误差，这是由于电流背景减除问题。特别是，当铁电薄膜的极化反转与铁电电阻行为相关联时，由于两种极化状态的I-V特性的失配，背景电流扣除是不准确的。相反，我们表明，通过非对称最小二乘减法去除背景电流，虽然不是完美的，给出了一个更好的估计所研究的样品的铁电性能。
英文摘要：
The nanoscopic characterization of ferroelectric thin films is crucial from their device application point of view. Standard characterization techniques are based on detecting the nanoscopic charge compensation current (switching current) caused by the polarization reversal in the ferroelectric. Owing to various surface and bulk limited mechanisms, leakage currents commonly appear during such measurements, which are frequently subtracted using the device I-V characteristic by employing positive-up-negative-down (PUND) measurement scheme. By performing nanoscopic switching current measurements on a commonly used ferroelectric, BiFeO3, we show that such characterization methods may be prone to large errors in the polarization estimation on ferro-resistive samples, due to current background subtraction issues. Especially, when ferro-resistive behavior is associated with the polarization reversal of the ferroelectric thin film, background current subtraction is not accurate due to the mismatch of the I-V characteristics for the two polarization states. We show instead that removing the background current by an asymmetric least squares subtraction method, though not perfect, gives a much better estimation of the ferroelectric properties of the sample under study.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
