Faraday Effect

If using a laser light source instead of white light, ensure appropriate laser safety protocols are followed. Even Class 2 lasers require avoiding direct eye exposure and specular reflections. Post appropriate laser safety signage if using Class 3 or higher lasers.

Strong electromagnets or permanent magnets can affect nearby electronic devices, credit cards, and magnetic media. Keep sensitive equipment at least 30 cm away. Warn anyone with pacemakers or other medical implants before energizing strong electromagnets.

Purpose

An applied magnetic field rotates the plane of polarization of light passing through a transparent medium, demonstrating the Faraday effect. Students observe the non-reciprocal magneto-optical rotation and its dependence on field strength.

Vintage Faraday effect apparatus: power supply on left, electronics controller in center, electromagnet assembly with two coils and gap for the Faraday cell, and circular polarizer/analyzer on right

Figure 1:

Warning: Laser Safety

Warning: Magnetic Field Awareness

Purpose

Safety Warnings

Warning: Laser Safety

Warning: Magnetic Field Awareness

Purpose