POC-OC-122464-Terbium Gallium Garnet Crystal

  • High Verdet constant (35 Rad T^-1 m^-1) for excellent magneto-optical performance.
  • High thermal conductivity (7.4 W m^-1 K^-1), ensuring efficient heat dissipation.
  • Superior laser damage threshold (>1 GW/cm²) for high-power laser systems.
  • Low optical loss (<0.1%/cm), minimizing light absorption.
  • Broad application range from 400 nm to 1100 nm (excluding 475 nm–500 nm).

Customizable Components Available for This Material to Meet Your Specific Needs!

TGG Crystal Material General Description

Terbium Gallium Garnet (TGG Crystal) is a high-performance magneto-optical crystal widely used in Faraday devices, including optical isolators and rotators. This cubic crystal system offers a unique combination of high thermal conductivity, low optical loss, and excellent Verdet constant, making it the material of choice for optical systems requiring high power and precision. TGG crystals are especially suitable for multi-stage laser amplification systems and ring-type laser cavities due to their robustness and optical clarity. With its high laser damage threshold, TGG ensures stable performance in demanding applications, including industrial and scientific laser systems.

TGG Crystal General Applications

  1. Optical Isolators and Rotators
    TGG crystals are primarily used in Faraday isolators and rotators, essential for protecting laser systems by isolating back-reflected light. Their high Verdet constant enhances their efficiency in these devices.
  2. Laser Systems
    TGG is commonly used in high-power laser applications where thermal management and optical quality are crucial. Applications include YAG and Ti:Sapphire lasers in industrial cutting, welding, and research systems.
  3. Ring Laser Systems
    The low absorption and high thermal conductivity of TGG make it ideal for ring laser gyroscopes and amplifiers requiring stable and consistent performance over extended use.
  4. Environmental and Scientific Instruments
    TGG crystals are used in magneto-optical spectrometry and environmental monitoring systems to manipulate light polarization in highly accurate setups.

Chemical and Structural Properties

Property

Value

Chemical Formula

Tb3Ga5O12

Crystal Structure

Cubic

Lattice Constant

12.355 Å

Density

7.13 g/cm³

Melting Point

1725°C

Mohs Hardness

8.0

Thermal Conductivity

7.4 W m^-1 K^-1

Laser Damage Threshold

>1 GW/cm²

Refractive Index @1064 nm

1.954

Optical, Laser and Nonlinear Optical Properties

Property

Value

Verdet Constant

35 Rad T^-1 m^-1

Wavelength Range

400 nm–1100 nm

Transmission Loss

<0.1%/cm

Absorption Bandwidth

Broad

Thermal Expansion Coefficient

7.4 × 10^-6 K^-1

Standard Fabrication Specifications

Specification

Value

Orientation

[111] within ±15′

Extinction Ratio

>30 dB

Diameter Tolerance

±0.1 mm

Length Tolerance

±0.2 mm

Surface Quality (Scratch/Dig)

10/5 (MIL-PRF-13830B)

Flatness

≤λ/8 @ 633 nm

Wavefront Distortion

≤λ/8 @ 633 nm

Parallelism

20 arc sec

Perpendicularity

15 arc min

Chamfer

0.2 mm × 45°

AR Coating

<0.2% @ 1064 nm

Spectrum Transmission Curve:

Coating Specification:

 

  • Anti-Reflective (AR) coating options available for specific laser wavelengths.
  • Typical coatings include <0.2% reflectivity at 1064 nm.
  • Adhesion Test Compliant with MIL-C-675C military standards, an adhesion test involved applying a tape that meets LT-90 specifications onto the lens film layer. The tape was affixed fully and then removed vertically. This procedure was performed three times, resulting in no blistering or peeling.
  • Temperature Test In line with MIL-C-675C specifications, test pieces were subjected to temperatures of -62±1℃ and 71±1℃. After maintaining them at room temperature (16℃~32℃) for two hours, the adhesion test was repeated, confirming no film detachment.
  • Abrasion Resistance Test Conforming to MIL-C-675C and CCC-C-440 standards, the abrasion resistance test involved a gauze tester applying a minimum force of 1.0 lbs (0.45 kg) to the film. This was repeated 25 times with gauze widths of 1/4 inch (6.4mm) and 3/8 inch (9.5mm), ensuring no damage occurred to the film surface.
  • Humidity Test Under MIL-C-675C criteria, the test piece was placed in a controlled temperature and humidity chamber set to 49 ±2℃ and 95%~100% humidity for 24 hours. The film remained intact, with no peeling, scratches, or other defects.
  • Solvent and Cleaning Testing Following MIL-C-675C specifications, test pieces were exposed to room temperature conditions (16℃~32℃) and tested with acetone and alcohol for at least 10 minutes each. After air drying and subsequent cleaning with a cotton cloth soaked in alcohol, the film surface showed no signs of peeling or scratches.
  • Salt Spray Test After 100 hours in a 35°C environment with a 5% saltwater concentration, the film showed no signs of damage.

POC Strength and Capabilities

 

Photonics On Crystals (POC) specializes in manufacturing high-quality TGG crystals with precise tolerances and tailored coatings for specific applications. POC ensures rigorous quality control standards and offers customization services to meet client-specific requirements. With advanced fabrication techniques and a commitment to excellence, POC delivers industry-leading TGG crystals for scientific and industrial applications.

Standard Products

Face Dimensions (mm)

Length (mm)

Coatings

Price (USD)

3 × 3

5

Uncoated

370

3 × 3

5

AR@1064 nm

435

Custom Size

Custom

Coating as required

Request