Compact Fiber-Optic Current Sensor With a Polarization Splitter and a 22.5$^\circ$ Faraday Rotator

In this letter, a novel implementation of a polarimetric fiber-optic current sensor scheme based on polarizing beam splitter and a
$22.5^{\circ }$
Faraday rotator will be presented. The developed sensor employs a compact and pigtailed component realized by joining a polarizing beam splitter and a Faraday rotator, it does not require any external adjustment to work and shows very high immunity to external electromagnetic and mechanical interference. The experimental results prove good sensitivity of the sensor allowing for the measurement of small value of current down to 100 mA.