Electric field sensing with a hybrid polymer/glass fiber

We demonstrate the operation of an in-fiber electric field sensor. The sensor is fabricated with selective chemical etching of the core of a D-shaped optical fiber followed by the deposition of an electro-optic polymer (PMMA∕DR1), which forms a hybrid core. The device demonstrates electromagnetic field sensitivity less than $100\text{V}/\text{m}$ at a frequency of $2.9\text{\hspace{0.17em} GHz}$. $E_{\pi }$ is estimated to be $60\text{MV}/\text{m}$ with an insertion loss of $14.4\text{\hspace{0.17em} dB}$.