Whispering gallery mode microcavities for photonic sensing applications

光与它所接触的一切相互作用。当光穿过物质或从表面反射时，其性质会受到影响，从而提供有关环境的重要信息。光子传感器使用光来“感知”周围的环境，其长度尺度非常微小。小是重要的;它可以降低成本，增加“现场”操作的便携性，快速产生结果，并最大限度地减少对大型和昂贵实验室的需求。光子传感器可用于相当广泛的应用，并且正在由世界各地的研究小组和公司开发。应用范围从手持式有毒气体传感器到检测高危人群的疾病。然而，制造用于特定应用的光子传感器可能是困难的。许多相互竞争的效应可能会“重叠”，使得难以检测到感兴趣的特定物质的存在。许多分析物在化学上是复杂的（例如，血液），并且很难仅对一个特定目标进行选择性。此外，通常必须检测非常弱的信号。

Light interacts with everything it touches. Whenever light passes through a substance or reflects from a surface, its properties are affected in ways that can give important information about the environment. Photonic sensors use light to “sense” the surroundings on a length scale that is truly tiny. Being small is important; it can reduce cost, increase portability for operation “in the field”, yield fast results, and minimize the need for large and expensive laboratories. Photonic sensors can be used in a considerable range of applications and are being developed by research groups and companies worldwide. Applications range from hand-held toxic gas sensors to the detection of disease in at-risk populations. Making a photonic sensor for a particular application can be difficult, however. Many competing effects can “overlap”, making it hard to detect the presence of the specific substance of interest. Many analytes are chemically complex (e.g., blood), and it is hard to be selective for only one specific target. Also, one must typically detect very weak signals.