Surface-enhanced Raman scattering (SERS) substrates based on chemical mechanism (CM) have received widespread attentions for the stable and repeatable signal output due to their excellent chemical stability, uniform molecular adsorption and controllable molecular orientation. However, it remains huge challenges to achieve the optimal SERS signal for diverse molecules with different band structures on the same substrate. Herein, we demonstrate a graphene oxide (GO) energy band regulation strategy through ferroelectric polarization to facilitate the charge transfer process for improving SERS activity. The Fermi level (E_f) of GO can be flexibly manipulated by adjusting the ferroelectric polarization direction or the temperature of the ferroelectric substrate. Experimentally, kelvin probe force microscopy (KPFM) is employed to quantitatively analyze the E_f of GO. Theoretically, the density functional theory calculations are also performed to verify the proposed modulation mechanism. Consequently, the SERS response of probe molecules with different band structures (R6G, CV, MB, PNTP) can be improved through polarization direction or temperature changes without the necessity to redesign the SERS substrate. This work provides a novel insight into the SERS substrate design based on CM and is expected to be applied to other two-dimensional materials.

能量分辨中子成像谱仪是中国散裂中子源当前在建的谱仪之一，其衍射探测器90°分区采用⁶LiF/ZnS中子闪烁体探测器作为探测设备。为实现探测器高位置分辨，读出电子学系统采用了一种电容网络复合读出电路和电荷重心法相结合的实现方法，并研制了电子学样机。该样机由电容网络复合读出电路、前置放大板和数字读出板三部分组成，基本功能验证完成后，分别在实验室和中国散裂中子源的20号束线上进行了相关性能参数测试，测试结果显示：电子学的积分非线性≤0.95%，时间分辨约为12 ns；探测器位置分辨为1 mm、探测效率为65%@1.6 ?，均达到了工程设计指标。该样机的成功研制为能量分辨中子成像谱仪未来顺利开展谱仪实验提供了可靠的技术保障。

通过理论推导和模拟试验，研究了单光子和双光子吸收分别占主导时，脉冲激光模拟试验中电荷收集效率之间的定量关系。分析不同光学参数对模拟试验中电离电荷浓度影响，确定具体激光波长、脉宽、能量及束斑等参数。根据脉冲激光在硅中单光子线性吸收和双光子非线性吸收的特点，推导单光子与双光子吸收产生电荷量比值的定量公式。通过1064 nm和1200 nm波长激光的验证试验，发现了响应脉冲及产生电荷量与脉冲激光能量或能量平方具有良好的线性关系，且在单光子吸收和双光子吸收各自占主导时，单光子吸收产生电荷率明显高于双光子吸收，证明了两种波长激光产生电荷量的比值近似等于公式计算结果。结果表明，1200 nm脉冲激光 1 nJ² 诱导电荷量等同于1064 nm脉冲激光 0.039 nJ诱导电荷量。