The Ho:Cr:Tm:YAG Crystal (Holmium, Chromium, Thulium co-doped Yttrium Aluminum Garnet) crystal is a high-efficiency laser material emitting at a wavelength of 2.1 µm. This emission wavelength is particularly valuable for medical, atmospheric, and industrial applications due to its position in the eye-safe range and its compatibility with biological tissues.
The co-doping of Ho, Cr, and Tm ions enhances energy transfer, reduces the lasing threshold, and improves slope efficiency. The Cr ions act as sensitizers, absorbing pump energy efficiently and transferring it to the Tm ions, which subsequently transfer the energy to the Ho ions for final laser emission. This process ensures high efficiency and excellent thermal stability, making Ho:Cr:Tm:YAG a preferred material for CW and pulsed lasers.
With its ability to be pumped by flashlamps or diodes, combined with high optical quality and thermal conductivity, this crystal meets the demanding requirements of modern laser systems.
Property | Specification |
Crystal Structure | Cubic Garnet |
Chemical Formula | Ho:Cr:Tm:Y3Al5O12 |
Growth Method | Czochralski |
Density | 4.56 g/cm³ |
Dopant Concentration | Ho: 0.35 at.%, Cr: 1.5 at.%, Tm: 5.8 at.% |
Refractive Index | 1.80 @ 2.08 µm |
Thermal Conductivity | 12 W/m/K |
Thermal Expansion Coefficient | 7.8 × 10^-6 K⁻¹ |
Hardness | 8.5 Mohs |
Optical Homogeneity | < λ/10 |
Melting Point | 1970 °C |
Parameter | Specification |
Laser Transition | ^5I7 → ^5I8 |
Laser Wavelength | 2.097 µm |
Photon Energy | 9.55 × 10^-20 J |
Emission Cross Section | 7 × 10^-20 cm² |
Fluorescence Lifetime | 8.5 ms |
Absorption Linewidth | 4 nm |
Diode Pump Band | 781 nm |
Major Pump Bands | 400–800 nm |
Mode of Operation | CW, Pulsed |
Specification | Value |
Rod Dimensions | Diameter: 3–6 mm, Length: 50–120 mm |
Surface Quality | 10/5 scratch-dig per MIL-PRF-13830B |
Flatness | A/8 @ 633 nm |
Parallelism | <30 arc sec |
Perpendicularity | <15 arc min |
Chamfer | 0.2 mm × 45° |
Mounting | Unmounted |
Ho:Cr:Tm:YAG exhibits strong absorption at 781 nm for efficient pumping and high emission at 2.1 µm, ensuring optimal energy transfer and emission stability. The crystal supports eye-safe laser operation with minimal thermal distortion.
| Dimensions | Length | End Faces | Doping | Coating | Price (USD) |
|---|---|---|---|---|---|
| 3 × 3 mm | 10 mm | Brewster-angle cut | Ho: 0.35%, Cr: 1.5%, Tm: 5.8% | AR-coated @ 2.1 µm | $720 |
| 5 × 5 mm | 20 mm | Right-angle cut | Ho: 0.35%, Cr: 1.5%, Tm: 5.8% | AR-coated @ 2.1 µm | $850 |
| 10 × 10 mm | 50 mm | Brewster-angle cut | Ho: 0.35%, Cr: 1.5%, Tm: 5.8% | Custom Coating | $1050 |
| Customization | As needed | As needed | As requested | As requested | Request Quote |