随着人们对于环境问题的关注度逐渐提高，如何有效准确地检测空气中气体成分与浓度的变化，成为了环境治理工作的关键。红外探测器以其性能稳强、灵敏度高、选择性好、动态测量范围大等优点广泛应用于气体探测领域。然而，目前的红外气敏探测器只能借由分立滤光片对探测波长进行选择，很难实现多种气体同时检测的功能。本项目创新性地提出自结晶生长的Au/Si核壳结构纳米天线阵列的新型光热耦合结构，用以实现具有窄带滤波功能的宽频可调红外热释电探测器。该新型光热耦合结构借由核壳结构的光学谐振效果增强光吸收的同时，通过其壳核比的调控突破了金属纳米天线只能通过形貌改变实现光吸收波段控制的限制。本项目通过对Au/Si核壳结构纳米天线的结晶规律以及其形貌结构与光波耦合的内在联系的研究为红外气敏探测器在性能与尺度上的改进提出了全新的思路，对推动气体探测技术发展具有重要意义。

With the increased concern on environment problems, how to detect the composition and concentration change of gas in air effectively and accurately has become crucial issue for the environmental improvement. Infrared gas sensors have been widely engaged in gas detection owing to their high stability, sensitivity, spectral selectivity, large dynamical sensing range, and etc. However, infrared gas sensors have to work with various discrete optical filters in air to select a certain characteristic wavelength for each gas. Therefore, we propose a novel nanostructure of Au/Si core-shell nanoatenna arrays fabricated via self-crystallization for energy conversion from light to heat, which can be applied in the IR pyroelectric detector with a tunable sensing wavelength in a broadband range. This novel nanostructure can efficiently enhance the light absorption via the surface plasmon resonance, and provide a new approach for sensing wavelength selection via the control of core shell ratio rather than simply via the control of the configuration of the nanoantenna. We systematically investigate the evolution on the growth of nanoantenna and the related optical properties, which offers a new way to optimize the performance and minimize the size of IR gas detector. This proposal can significantly affect the innovation on gas sensing.