Faraday rotators and isolators are key components of an optical fiber system when it comes to transmitting light signals in different polarized states. The polarized state of a light signal is an important characteristic you need to focus on for effective signal transmission. Optical engineers use a high-power Faraday rotator and isolator to take care of it during the system design. In this post, we will discuss both the products and their application in optical systems.
Faraday Rotator
Faraday rotator is a magneto-optic device that uses the Faraday Effect to rotate the polarization state of transmitted light. The light signal travels through a transparent medium exposed to a magnetic field to change the polarization state. The direction of the magnetic field is either the same as the direction of the transmitted light or opposite to it.
When a light signal passes through a Faraday rotator, its polarization state is continuously rotated through the medium. Every change in polarizations state adds up instead of canceling. This phenomenon is known as non-reciprocal behavior, which makes Faraday rotator distinct from arrangements like waveplates and polarizers.
Applications of Faraday Rotators
- Faraday Rotators are most widely used in optical laser applications. Some of the most common applications are:
- To protect lasers and amplifiers from back-reflected light.
- To introduce round-trip losses in ring laser resonators to enforce unidirectional operation. High-power Faraday rotators are capable of facilitating very small rotation angles as per specific requirements.
- Faraday rotators can be used in Faraday mirrors and interferometers.
Faraday Isolators
It is a typical optical isolator used in optical system designs to transmit light signals in specific directions. It also blocks the reflected light in the opposite direction. There are mainly two types of faraday isolators available – Polarization Sensitive Faraday Isolators and Polarization Insensitive Faraday Isolators used for specific purposes.
Applications of Faraday Isolators
- Like the Faraday rotators, faraday isolators are also used to protect amplifiers and lasers from back-reflected light. You can use several isolators in amplifier chains between different stages to achieve spontaneous emission.
- Faraday isolators are used within a laser resonator to enforce a linear polarization state.
- Faraday isolators are also used for mode-locking with polarization rotation in an optical fiber system.
High-power Faraday Rotator and Isolator are used for a variety of applications in a wide range of industries including telecommunication, instrument, automation, and electronics. At DK Photonics, you can purchase high-power Faraday rotators and isolators with standard settings and specifications. You can contact us for custom fiber solutions to meet your specific requirements if you don’t find a standard Faraday rotator or isolator in our catalog.