Erbium and ytterbium co-doped phosphate glass (Er:Yb:glass) crystal is a commonly used laser active medium that emits laser light in the "human eye safe" spectral range of 1.5 to 1.6 µm. Er3+/Yb3+ co-doped phosphate glasses with passive Q-modulated crystal eutectics can be used to obtain pulsed solid-state lasers at 1540 nm.
Lasers made with Er:Yb:glass crystal at 1540 nm can be used as eye-safe wavelength lasers. Alfa Chemistry is an expert in creating customized laser crystals, and will help clients through the online customizing process for Er:Yb:glass laser crystals with care and patience.
Advantages of Er:Yb:Glass Crystals
The Er3+ is the excited radiative ion whose most common laser leap occurs from the 4I13/2 manifold to the ground state manifold 4I15/2, which is a quasi-triple energy level leap in which the laser leap ends in the ground state.
Fig 1. Energy level transition diagram of Er:Yb:glass. (Qi Y, et al. 2021)
The absorption band of Er:Yb: glass crystal is weak and the absorption cross section near the absorption peak is small, resulting in a lower absorption efficiency of the pump beam. The Yb3+ ion absorbed by 2F7/2 → 2F5/2 leap is the most effective. This is followed by an energy transfer to the 4I11/2 Er3+ energy level and a quick nonradiative leap to the Er3+ 4I13/2 energy level, where the anticipated fluorescence is released.
Advantages:
- Wide absorption band
- Long fluorescence lifetime
- High optical quality
- High slope efficiency
- Safety for eye
Properties of Er:Yb:Glass Crystals
| Optical and Laser Properties | |
|---|---|
| Fluorescent Lifetime | 7.7~8.0 ms |
| Cross Section for Stimulated Emission | 0.8*10-20 cm2 |
| Refractive Index | (1535nm) 1.524; (589.3nm) 1.532 |
| Center Lasing Wavelength | 1535 nm |
| Transformation Temp. | 556 ℃ |
| Softening Temp. | 605 ℃ |
| dn/dT | -1.72*10-6/℃ (20~100 ℃) |
| Thermal Conductivity | (25 ℃) 0.7 W/mK |
| Density | 3.06 g/cm3 |
| Chemical Durability | 52 μg/hr.cm2 (weigh loss rate at 100 ℃ distilled water) |
| Coeff.of Linear Thermal Expansion | 87*10-7/K (20~100 ℃); 95*10-7/K (100~300 ℃) |
| Thermal Coeff.of Optical Path Length | 2.9*10-6/K (20~100 ℃) |
| Alfa Chemistry offers Er:Yb:glass specification | |
| Dimension | Upon customer request |
| Dimension Tolerance | Rods with diameter +0.0/-0.05 mm, L±0.1mm |
| Flatness | λ/8 @ 632.8nm |
| Surface Quality | 10/5 Scratch/Dig MIL-O-1380A |
| Clear Aperture | > 90% |
| Damage Threshold | 750MW/cm2 at 1064nm, TEM00, 10ns, 10Hz |
| Coating | AR/HR coating upon customer's request |
| Quality Warranty Period | One year under proper use |
Why Choose Alfa Chemistry?
Alfa Chemistry offers high quality Er3+/Yb3+ co-doped phosphate glass for human eye safety lasers. The size is tailored to the client's requirements. Other related high laser induced damage threshold cavity lenses and mirrors for human eye safety lasers are also available from stock.
Fig 2. Common passively Q-switches used for Er:Yb:glass lasers. (Qi Y, et al. 2021)
If you need technical advice, please contact our technical team to learn more about our high-quality services.
Reference
- Qi Y, et al. (2021). "Research Progress of All-Solid-State Passively Q-switched Er:Yb:Glass Lasers." Infrared Physics & Technology. 116: 103727.