POC-OC-122445-Ho:YAG Crystal

  • High optical quality and conversion efficiency for superior laser performance.
  • Operates at 2090 nm, ideal for eye-safe wavelengths with high atmospheric transmittance.
  • Exceptional tissue penetration for medical applications with minimal surrounding damage.
  • Applicable for mid-IR nonlinear effects, enabling wavelengths of 3–5 µm.
  • High extinction ratio (>28 dB) ensures precision and minimal optical losses.

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

Ho:YAG Crystal Material General Description

Holmium-doped Yttrium Aluminum Garnet (Ho:YAG) crystals offer advanced functionality in the field of mid-infrared (IR) laser systems. The 2090 nm emission wavelength lies within an atmospheric transparency window and aligns with the water absorption peak in human tissues, making Ho:YAG indispensable in medical, sensing, and laser rangefinding applications.

Ho:YAG is also preferred in medical laser surgeries for precise tissue ablation with minimal collateral damage, penetrating only a few microns. It has excellent thermal conductivity, ensuring stability during prolonged operations. Additionally, the crystal is utilized in nonlinear optical systems to achieve wavelengths in the 3–5 µm range for extended IR applications.

 

Ho:YAG Crystal General Application and Examples

Ho:YAG crystals are versatile and widely used in applications including:

  • Medical Applications: High-precision tissue ablation for surgical procedures such as urology and dermatology, benefiting from the shallow tissue penetration and minimized thermal damage.
  • Atmospheric Sensing: Ho:YAG Crystal lasers’ mid-IR wavelengths allow for high-resolution sensing and probing in atmospheric research, leveraging its strong absorption at water vapor peaks.
  • Industrial Applications: Cutting-edge laser rangefinding, welding, and microfabrication take advantage of Ho:YAG’s robust beam quality.
  • Nonlinear Optics: Enabling wavelengths of 3–5 µm by coupling Ho:YAG lasers with ZGP crystals for specialized IR applications.
  • Military Applications: Rangefinding, target designation, and secure optical communication systems.

Chemical and Structural Properties

Property

Value

Crystal Formula

Ho:YAG (Y3Al5O12)

Crystal Structure

Cubic, <111> Orientation

Lattice Parameter

12.01 Å

Melting Point

1970 °C

Density

4.56 g/cm³

Mohs Hardness

8.5

Thermal Conductivity

10 W/m·K

Thermal Expansion

8.1 × 10^-6/K

Specific Heat

0.65 J/g·K

Extinction Ratio

>28 dB

Optical, Laser and Nonlinear Optical Properties

Property

Value

Emission Wavelength

2090 nm

Refractive Index

1.82

Fluorescence Lifetime

8 ms

Absorption Peak Wavelength

1900 nm

Pumping Wavelength

1940 nm

Laser Transition

5I7 to 5I8

Optical Clarity (Transmission)

>90%

Standard Fabrication Specifications

Parameter

Specification

Orientation

<111>

Diameter Tolerance

+0/-0.05 mm

Length Tolerance

±0.5 mm

Surface Flatness

λ/10 @ 632 nm

Parallelism

<10 arc sec

Perpendicularity

<5 arc min

Surface Quality (Scratch/Dig)

10-5

Clear Aperture

>90%

Chamfer

0.1 mm x 45°

Spectrum Transmission Curve:

Due to Ho:YAG’s superior optical clarity, transmission spectra exhibit high transmittance at 2090 nm, with minimal loss across the mid-IR region. This is ideal for medical lasers requiring precise wavelength control. If additional details are required, POC can provide custom data.

Coating Specification:

 

  • AR Coating: Custom anti-reflection coatings available for 2094 nm and adjacent wavelengths.
  • Standard: Reflectivity < 0.2% @ 2094 nm.
  • Coating Durability: High threshold coatings for durability under high-power operations.
  • 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) offers Ho:YAG crystals with unparalleled precision and performance. POC’s state-of-the-art facilities ensure strict quality control and consistent production standards. Our expertise in crystal growth and custom fabrication allows us to cater to a variety of customer needs, including:

  • Custom doping levels.
  • Precision dimensions for medical and industrial-grade systems.
  • Advanced AR and HR coatings.

POC is committed to delivering high-performance Ho:YAG crystals for global markets, ensuring customer satisfaction with tailored solutions.

Standard Products

Dimension

Length

End Faces

Coating

Price (USD)

3 x 3 mm

10 mm

Brewster

AR @ 2094 nm

Request

5 x 5 mm

15 mm

Flat/Flat

Uncoated

Request

8 x 8 mm

20 mm

Brewster

AR/HR @ 2090 nm

Request

Custom

Custom

Custom

Custom

Request