A Narrowband Photo‐Thermoelectric Detector Using Photonic Crystal
A Narrowband Photo‐Thermoelectric Detector Using Photonic Crystal
复制标题
DOI：
10.1002/adom.201801248
复制
发表时间：
2018-12
影响因子：
9
通讯作者：
H. Monshat;Longju Liu;Meng Lu
中科院分区：
文献类型：
--
作者：
H. Monshat;Longju Liu;Meng Lu
在这里，报道了一种波长特定的光电（PTE）器件，其使用光栅图案化衬底上的薄膜堆叠来实现窄带光吸收和热电转换功能。传统的PTE器件是宽带的，吸收从紫外到太赫兹的电磁辐射。存在对能够在期望波长处展现窄带响应的PTE装置的需求。在这里，窄带PTE器件由带金属包层的光子晶体（PC）滤波器和薄膜热电偶组成。对PC-PTE设计进行了数值研究，以说明潜在的能量转换机制。该装置是使用nanoreplica成型，然后由薄膜涂层制造。所制备的金属包层PC谐振器在可见光波长范围内表现出窄带光吸收，谐振吸收系数为85.4%，半高宽为14.8 nm。PTE测量表明，热电输出对入射光和导模共振模式的耦合敏感。在谐振条件下照明，PTE器件的响应度和噪声等效功率分别为0.26 V W−1和7.5 nW Hz−1/2。这种PC-PTE技术具有窄带检测、大表面积和低成本的独特属性，可用于传感器、光谱学和成像领域。
Here, a wavelength‐specific photo‐thermoelectric (PTE) device is reported that achieves narrowband optical absorption and thermoelectric conversion functions using a stack of thin films on a grating‐patterned substrate. Conventional PTE devices are broadband with the absorption of electromagnetic radiation from ultraviolet to terahertz. There are demands for PTE devices that can exhibit narrowband response at a desired wavelength. Here, the narrowband PTE device consists of a photonic crystal (PC) filter with metal cladding and a thin‐film thermocouple. The PC‐PTE design is investigated numerically to illustrate the underlying energy conversion mechanism. The device is fabricated using nanoreplica molding followed by coating of thin films. The fabricated metal‐cladding PC resonator exhibits a narrowband optical absorption with a resonant absorption coefficient of 85.4% and full‐width‐half‐maximum of 14.8 nm in the visible wavelength range. The PTE measurements show that the thermoelectric output is sensitive to the coupling of incident light and guided‐mode resonance modes. Illuminated under the resonant condition, the PTE device exhibits a responsivity and noise equivalent power of 0.26 V W−1 and 7.5 nW Hz−1/2, respectively. This PC‐PTE technology has the unique attributes of narrowband detection, large surface area, and low cost for the potential application in sensors, optical spectroscopy, and imaging.