Peter-Grünberg-Institute (PGI-8), Forschungszentrum Jülich, Jülich 52425, Germany.
Nano Lett. 2016 Apr 13;16(4):2295-300. doi: 10.1021/acs.nanolett.5b04729. Epub 2016 Mar 3.
In this Letter, the ambipolar properties of an electrolyte-gated graphene field-effect transistor (GFET) have been explored to fabricate frequency-doubling biochemical sensor devices. By biasing the ambipolar GFETs in a common-source configuration, an input sinusoidal voltage at frequency f applied to the electrolyte gate can be rectified to a sinusoidal wave at frequency 2f at the drain electrode. The extraordinary high carrier mobility of graphene and the strong electrolyte gate coupling provide the graphene ambipolar frequency doubler an unprecedented unity gain, as well as a detection limit of ∼4 pM for 11-mer single strand DNA molecules in 1 mM PBS buffer solution. Combined with an improved drift characteristics and an enhanced low-frequency 1/f noise performance by sampling at doubled frequency, this good detection limit suggests the graphene ambipolar frequency doubler a highly promising biochemical sensing platform.
在这封信件中，我们探讨了栅极电压控制的双极性石墨烯场效应晶体管（GFET）的双极性性质，以构建倍频生化传感器设备。通过在共源配置中对双极性 GFET 施加偏置，施加到电解质栅极的频率为 f 的输入正弦电压可以被整流为频率为 2f 的正弦波，出现在漏电极上。石墨烯极高的载流子迁移率和强电解质栅极耦合使石墨烯双极性倍频器具有前所未有的单位增益，以及在 1mM PBS 缓冲溶液中对 11 聚体单链 DNA 分子的检测限约为 4pM。通过在两倍频率下采样来改善漂移特性和增强低频 1/f 噪声性能，这种良好的检测限表明石墨烯双极性倍频器是一种很有前途的生化传感平台。
