Impurity charge compensation in graphene by a polarized ferroelectric polymer and its effect on charge transport near the Dirac point
Impurity charge compensation in graphene by a polarized ferroelectric polymer and its effect on charge transport near the Dirac point
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DOI：
10.1063/5.0054083
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发表时间：
2021-08
期刊：
影响因子：
1.6
通讯作者：
Kelotchi S. Figueroa;N. Zimbovskaya;N. Pinto;C. Wen;A. T. Johnson
中科院分区：
文献类型：
--
作者：
Kelotchi S. Figueroa;N. Zimbovskaya;N. Pinto;C. Wen;A. T. Johnson
在300 < T < 350 K的温度范围内，利用铁电（FE）门控研究了石墨烯中Dirac点（DP）附近的电荷输运。我们观察到DP附近的电导率（σ）有一个正的温度梯度，随着温度的升高而变为负的温度梯度。向负温度梯度的转换转移到更高的温度，并在远离DP时逐渐减弱。通过FE极化和石墨烯-杂质电荷分离的杂质电荷补偿被认为是造成σ(T)非单调性的原因。石墨烯输运中掺杂杂质电荷散射和声子散射的自一致理论对结果进行了分析。残余电导率（σr）随温度的变化也存在非单调电荷输运现象。对σ和σr的理论分析表明，温度无关的贡献为~ 1.16e2h，这可能是原始石墨烯固有的。
Charge transport near the Dirac point (DP) was investigated in graphene using ferroelectric (FE) gating in the temperature range of 300 < T < 350 K. We observed that the conductivity (σ) near the DP had a positive temperature gradient that switched to a negative temperature gradient with increasing temperature. The switch to a negative temperature gradient shifted to higher temperatures and gradually weakened upon moving away from the DP. Impurity charge compensation via polarization of the FE together with a temperature-dependent graphene–impurity charge separation was proposed as being responsible for the non-monotonicity in σ(T). A self-consistent theory for graphene transport with impurity charge scattering and phonon scattering was used to analyze the results. Non-monotonic charge transport was also observed in the temperature dependence of the residual conductivity (σr). Theoretical analysis of both σ and σr revealed a temperature independent contribution of ∼1.16e2h that is probably inherent to pristine graphene.