Magneto-optical crystals

Magneto-optical crystals are essential for controlling light polarization through the Faraday effect, enabling precise operations in isolators, circulators, modulators, and other photonic applications. These crystals, vital in laser systems and optical communication networks, rotate light polarization under a magnetic field, ensuring superior performance in high-power and high-precision systems.

We focus on two leading materials—Terbium Gallium Garnet (TGG) and Terbium Scandium Aluminum Garnet (TSAG)—highlighting their features, specifications, and applications.

comparison table between TGG & TSAG

Verdet Constant
High
Superior (higher than TGG)
Transparency Range (nm)
400 - 1100 (visible to near-IR)
400 - 1600 (visible to mid-IR)
Thermal Conductivity
Excellent
Excellent
Optical Loss
Low
Lower than TGG
Damage Threshold
High
Enhanced (higher than TGG)
Key Features
High thermal stability, low signal attenuation, ideal for compact devices
Extended transparency range, ideal for infrared applications
Applications
Optical isolators, circulators, modulators, high-power lasers
Advanced optical isolators, fiber-optic communication, quantum optics, high-power lasers

Terbium Gallium Garnet (TGG)

TGG is a highly valued magneto-optical crystal known for its strong Faraday effect, low optical losses, and high Verdet constant. With excellent thermal conductivity and a robust damage threshold, TGG is ideal for optical isolators and circulators, offering broad optical transparency for both visible and infrared laser systems.

Key Features

  • High Verdet Constant

    Enables efficient Faraday rotation, even in compact device configurations.

  • Low Optical Loss

    Ensures minimal signal attenuation, crucial for high-power laser systems.

  • Thermal Stability

    Exceptional thermal conductivity supports stable performance in high-power operations.

  • Broad Transparency Range

    Operates from 400 nm to 1100 nm, covering visible to near-infrared regions.

  • High Damage Threshold

    Can withstand high-power laser beams without compromising optical quality.

Applications

  • Optical Isolators

    Prevents back-reflected light from damaging laser sources.

  • Optical Circulators

    Enables unidirectional signal propagation in fiber-optic systems.

  • Modulators and Sensors

    Provides precise light polarization control for advanced instrumentation.

  • High-power Lasers

    Delivers high performance in scientific, medical, and industrial laser systems.

Terbium Scandium Aluminum Garnet (TSAG)

TSAG is a next-generation magneto-optical crystal known for its superior Faraday rotation performance. With a higher Verdet constant and lower absorption losses than TGG, TSAG is quickly becoming the material of choice for advanced optical systems. Its extended transparency into the infrared makes it ideal for modern laser applications.

Key Features

  • Superior Verdet Constant

    Provides greater Faraday rotation compared to TGG for smaller and more compact device designs.

  • Low Absorption Loss

    Ensures minimal signal degradation, critical for high-precision systems.

  • High Thermal Stability

    Supports consistent performance under high-power laser conditions.

  • Extended Transparency Range

    Operates effectively from 400 nm to 1600 nm, covering visible to mid-infrared wavelengths.

  • Enhanced Damage Threshold

    Able to handle extreme laser intensities without degradation.

Applications

  • High-power Optical Isolators

    Ideal for laser technologies in industrial, scientific, and medical fields.

  • Advanced Laser Systems

    Enables precision in high-energy, high-pulse lasers.

  • Fiber-optic Communication

    Enhances signal integrity in long-distance optical networks.

  • Quantum Optics

    Facilitates research in quantum communication and computing technologies.