论文标题
负电容的铁电二电连接的频率依赖性介电响应
Frequency dependent dielectric response of ferroelectric-dielectric junction with negative electric capacitance
论文作者
论文摘要
我们计算了分层的铁电 - 二电连接的频率依赖性介电响应（电敏感性），并偏向于单个频率$ω$的时间依赖性谐波电压。在电容负电容的区域中，通过层之间的电荷边界条件稳定了工作点。静态敏感性$χ_0$为负，相对介电常数$ε_r$小于一个$，清楚地表明了由于电容负电容而导致铁电层的相反方向和极化。在有限的频率下，此标志在易感性的实际部分保留，从而获得了频率依赖性。同样，由于电场和极化之间的相位移位而产生频率依赖性假想部分。线性状态下该频率依赖性的类型是所谓的放松（Debye）响应，即$χ'（ω）=χ_0/（1+（1+（1+（τΩ）^2）$和$χ”（ω）=χ_0τΩ/（1+（1+（1+（τΩ）^2）$，$τ$是$τ$是$τ$的特定时间特定的firs firter of firroction firty ofercielt of firorection firtiment of firrocty of yrocty of yrocty in rection for yrocty of yroctife yrocty rectrict intorcielt。铁电batio $ _3 $和电介质al $ _2 $ o $ _3 $，获取材料参数的实验值，并针对线性响应理论的结果解决了非线性的作用。
We calculated the frequency dependent dielectric response (electric susceptibility) of layered ferroelectric-dielectric junction, biased by the time-dependent harmonic voltage with single frequency $ω$. Working point is stabilized, by the charge boundary condition between the layers, in the region with negative electric capacitance. The static susceptibility $χ_0$ is negative and relative dielectric constant $ε_r$ smaller than one, clearly indicating the opposite direction of electric field and polarization in the ferroelectric layer due to the negative electric capacitance. At finite frequencies this sign is preserved in real part of susceptibility which gains the frequency dependence. Also, frequency dependent imaginary part arises due to the phase shift between electric field and polarization. The type of that frequency dependence in linear regime is so-called relaxation (Debye) response, i.e. $χ'(ω)=χ_0/(1+(τω)^2)$ and $χ"(ω)=χ_0τω/(1+(τω)^2)$, where $τ$ is polarization switching time characteristic to ferroelectric material. In particular, we modeled the junction of ferroelectric BaTiO$_3$ and dielectric Al$_2$O$_3$, taking the experimental values of material parameters, and addressed the role of nonlinearity with respect to result of the linear response theory.
