论文标题
双轴菌株对超薄inse的巨型压电效应和强带隙可调性
Giant piezoresistive effect and strong band gap tunability in ultrathin InSe upon biaxial strain
论文作者
论文摘要
二维（2D）半导体的超薄性质和悬挂键的自由表面允许通过应变工程对其带隙进行重大修改。在这里，薄的INSE光电探测器设备是双轴拉伸的，发现应变时具有强的带隙可调性。在温度升高后通过底物膨胀来控制所施加的双轴应变，并通过拉曼光谱法证实了从底物到薄INSE的有效应变转移。双轴应变时的带隙变化是通过光致发光测量来确定的，发现量规系数高达约200 meV/％。我们进一步表征了双轴应变对INSE设备电气性能的影响。在黑暗状态下，在施加的应变时观察到电流的大幅度增加，这给出了〜450-1000的压电量规因子值，比其他2D材料和最先进的硅菌株测量值大约5-12倍。此外，INSE带隙的双轴应变调谐还以应变诱导的红移，以ΔEct-Off 〜173 MeV的频谱响应的频谱响应，以〜360 meV/％的应变速率转换，表明光电镜的光谱带谱的较强应变性可刺激性。
The ultrathin nature and dangling bonds free surface of two-dimensional (2D) semiconductors allow for significant modifications of their band gap through strain engineering. Here, thin InSe photodetector devices are biaxially stretched, finding, a strong band gap tunability upon strain. The applied biaxial strain is controlled through the substrate expansion upon temperature increase and the effective strain transfer from the substrate to the thin InSe is confirmed by Raman spectroscopy. The band gap change upon biaxial strain is determined through photoluminescence measurements, finding a gauge factor of up to ~200 meV/%. We further characterize the effect of biaxial strain on the electrical properties of the InSe devices. In the dark state, a large increase of the current is observed upon applied strain which gives a piezoresistive gauge factor value of ~450-1000, ~5-12 times larger than that of other 2D materials and of state-of-the-art silicon strain gauges. Moreover, the biaxial strain tuning of the InSe band gap also translates in a strain-induced redshift of the spectral response of our InSe photodetectors with ΔEcut-off ~173 meV at a rate of ~360 meV/% of strain, indicating a strong strain tunability of the spectral bandwidth of the photodetectors.
