Er:YLF crystals are a highly efficient gain medium for laser systems due to their low phonon frequency, which enhances luminescence quantum efficiency by minimizing non-radiative relaxations. These crystals exhibit a long laser-emitting level lifetime, making them suitable for high-energy storage in Q-switched laser systems. Furthermore, their broad transparency range, extending from the vacuum ultraviolet (VUV) to the mid-infrared region (~10 µm), enables diverse optical applications. The negative thermo-optic coefficient of Er:YLF crystals provides a critical advantage in thermal management by reducing thermal-lensing effects, thus ensuring beam stability even under high-pump-power conditions.
Er:YLF crystals find applications across various domains due to their versatile optical and thermal properties:
| Property | Value |
|---|---|
| Orientation | a-cut |
| Clear Aperture | >90% |
| Face Dimensions Tolerance | ±0.01 mm |
| Length Tolerance | ±0.1 mm |
| Parallelism Error | <20 arcsec |
| Perpendicularity Error | <10 arcmin |
| Protective Chamfers | <0.1 mm at 45° |
| Surface Quality | 20–10 S-D |
| Surface Flatness | λ/10 @ 632.8 nm |
| Density | 3.95 g/cm³ |
| Mohs Hardness | 5 |
| Thermal Conductivity | 5 W·m⁻¹·K⁻¹ |
| dn/dT | -2 × 10⁻⁶ K⁻¹ |
| Thermal Expansion Coefficient | 8 × 10⁻⁶ K⁻¹ |
| Refractive Index (@2070 nm) | nₐ = 1.442; nₑ = 1.446 |
| Typical Doping Level | 15 at.% |
| Property | Value |
|---|---|
| Absorption Peak Wavelength | 972 nm |
| Absorption Cross-Section | 28 × 10⁻²⁰ cm² |
| Absorption Bandwidth | ~1 nm |
| Laser Wavelength | 2810 nm |
| Lifetime of Er³⁺ Energy Level | 4 ms |
| Emission Cross-Section (@2800 nm) | 1.5 × 10⁻²⁰ cm² |
| Crystal Structure | Tetragonal |
| Specification | Value |
|---|---|
| Face Dimensions Tolerance | ±0.01 mm |
| Length Tolerance | ±0.1 mm |
| Surface Flatness | λ/10 @ 632.8 nm |
| Parallelism Error | <20 arcsec |
| Perpendicularity Error | <10 arcmin |
| Clear Aperture | >90% |
| Protective Chamfers | <0.1 mm at 45° |
| Surface Quality | 20–10 S-D |
The transmission spectrum demonstrates excellent transparency across a wide range from VUV to ~10 µm, facilitating various optical and laser applications. Specific transmission curves can be provided upon request based on user requirements.
| Face Dimensions | Length | End Faces | Coatings | Price (USD) |
|---|---|---|---|---|
| 3 × 3 mm | 8 mm | Right-angle cut | Uncoated | $540 |
| 3 × 3 mm | 8 mm | Brewster-angle cut | AR (custom request) | $540 |
| 8 mm × 8 mm | 2 mm | Right-angle cut | AR (custom request) | $680 |
