Passive Q-Switches
Cr⁴⁺:YAG Passive Q-Switch Crystals
Cr⁴⁺:YAG crystals for passive Q-switching in selected Nd- and Yb-doped lasers around 1 µm, with initial transmission and coatings specified for the application.
- Germany-based supplier and manufacturing partner
- Manufacturing to customer specifications
- Optical inspection and measurement against specified requirements
- From single components and prototypes to repeat supply
Product overview
Cr⁴⁺:YAG is a solid-state saturable absorber used for passive Q-switching in laser systems operating around 1 µm. Its absorption band extends from 800 nm to 1200 nm, with strong absorption in the 1 µm region. Depending on the gain medium, initial transmission, and cavity configuration, short pulse durations and high repetition rates can be achieved.
It is commonly used in diode-pumped and lamp-pumped Nd:YAG, Nd:YLF, Nd:YVO₄, and other Nd- or Yb-doped laser systems.
Cr⁴⁺:YAG can also be used in passively Q-switched Nd-based laser systems incorporating intracavity or subsequent frequency conversion. Depending on the laser design, this can include frequency-converted output at 532 nm, 355 nm, or 266 nm using nonlinear crystals such as KTP, LBO, or BBO.
Key advantages
Compared with traditional dye-based or color-center passive Q-switch materials, Cr⁴⁺:YAG provides a robust solid-state solution with:
- High optical damage threshold
- Good thermal conductivity
- Good chemical stability and long-term reliability
- Broad absorption band with strong ground-state absorption around 1 µm
- Easy integration into compact passively Q-switched laser designs
Typical specifications
| Available geometries | Round, square, and rectangular |
|---|---|
| Diameter | Ø3–12 mm |
| Square / rectangular sizes | 3 × 3 mm to 12 × 12 mm |
| Thickness | 0.1–12 mm |
| Orientation | [100] or [111] within 5° |
|---|---|
| Initial absorption coefficient | 0.5–6 cm⁻¹ at 1064 nm |
| Initial transmission | 5–95% at 1064 nm |
| Flatness | < λ/8 |
| Wavefront distortion | < λ/4 |
| Parallelism | < 30 arcsec |
| Surface quality | 20/10 scratch-dig |
| AR coating reflectivity | ≤0.2% at 1064 nm |
| Dimensional tolerance | ±0.1 mm |
Properties
- Chemical formula
- Cr⁴⁺:Y₃Al₅O₁₂
- Crystal structure
- Cubic
- Dopant level
- 0.5–3 mol%
- Hardness
- 8.5 Mohs
- Refractive index
- 1.82 at 1064 nm
- Damage threshold
- ≥500 MW/cm² (10 ns, 1 Hz at 1064 nm)
Typical applications
- Ophthalmic Nd:YAG laser systems
- Laser rangefinding systems
- Scientific and laboratory pulsed laser systems
- Passive Q-switching of Nd:YAG, Nd:YVO₄, Nd:YLF, and selected Yb-doped laser systems
- Compact passively Q-switched solid-state laser systems
View related products
Nd:YAG Laser Crystals
For diode-pumped and lamp-pumped lasers, with custom doping levels, dimensions, end-face geometries, and coatings.
Nd:YVO₄ Laser Crystals
For compact 1064 nm diode-pumped lasers, with strong pump absorption, high gain, and polarized emission.
Nd:YLF Laser Crystals
For 1047/1053 nm lasers, with options for custom dimensions, doping, orientation, and optical coatings.
Dye Acetate Q-Switch Foil
Passive Q-switch foils for selected legacy Nd:YAG laser systems, available with specified dimensions and unsaturated transmission.
RFQ PREPARATION
What to send for a quote
Please send your drawing or technical specification together with the following information.
- Initial transmission or absorption requirement
- Geometry and dimensions
- Surface quality and optical tolerances
- Coating and wavelength requirements
- Required quantity