The electrically sensing characteristics of a liquid-crystal (LC)-infiltrated polarization-maintaining photonic crystal fiber (PCF) have been studied. The small holes on the end face of the fiber collapse and two large holes remain open by controlling discharging-time, -current, and -position of a fiber splicer, then LC is selectively infiltrated into the two large holes, which can not only save LC but also make the welding between the LC-infiltrated polarization-maintaining PCF and single-mode fiber much easier. A new method to weld the two fibers is proposed by filling and volatilizing ethanol to make LC a few millimeters away from the end face which can improve the sensing system stability and prevent the discharge of a fiber splicer from destroying LC molecules. A Sagnac interferometer is set up by embedding the LC-infiltrated polarization-maintaining PCF in a fiber loop and then its electroresponse characteristics are studied. The refractive-index distribution of the LC-infiltrated polarization-maintaining PCF varies with electric voltage due to the variable index of LC, which makes it possible to detect voltage. Three voltage ranges are discussed by the different dips and the sensitivity is improved with voltage increasing. The high sensitivity is up to 3.49 nm/V with the tuning range of 7 nm as voltage changes from 149.67 to 151.61 V. The Sagnac interferometer embedded with an LC-infiltrated polarization-maintaining PCF can be utilized as a voltage sensor, electro-optical modulator, or filter.

中文翻译：

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嵌入液晶渗透光子晶体光纤的萨格纳克干涉仪的电传感特性


研究了液晶（LC）渗透保偏光子晶体光纤（PCF）的电传感特性。通过控制熔接机的放电时间、电流和位置，使光纤塌陷端面的小孔和两个大孔保持打开状态，然后LC有选择地渗透到两个大孔中，这样不仅可以节省LC 还使得 LC 渗透保偏 PCF 和单模光纤之间的焊接更加容易。提出了一种焊接两根光纤的新方法，通过填充并挥发乙醇，使LC距离端面几毫米，可以提高传感系统的稳定性，并防止光纤熔接器的放电破坏LC分子。将液晶渗透保偏PCF嵌入光纤环中搭建了萨格纳克干涉仪，并研究了其电响应特性。由于液晶折射率可变，液晶渗透保偏PCF的折射率分布随电压变化，从而可以检测电压。通过不同的下降讨论了三个电压范围，并且灵敏度随着电压的增加而提高。当电压从 149.67 V 变化到 151.61 V 时，灵敏度高达 3.49 nm/V，调谐范围为 7 nm。嵌入 LC 渗透保偏 PCF 的 Sagnac 干涉仪可用作电压传感器、电光传感器调制器或滤波器。