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BaGa4Se7 BGSe --used

POC-OC-122418-BaGa4Se7 Crystal

  • Wide transmission range from 0.47 μm to 18 μm.
  • High nonlinear optical coefficient (dmax = 24.3 pm/V).
  • Excellent transparency with low absorption coefficients.
  • High damage threshold, suitable for high-power applications.
  • Ideal for mid-infrared applications, including spectroscopy and OPA/OPO systems.

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

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General Description

BaGa4Se7 Crystal, abbreviated as BGSe Crystal, is an advanced nonlinear infrared optical crystal characterized by its broad transmission range (0.47–18 μm) and high transparency. It exhibits a nonlinear coefficient approximately 2–3 times higher than AgGaS2 Crystals and a damage threshold roughly 3.7 times higher than traditional AgGaS2 materials. The crystal’s peak nonlinear coefficient, dmax, reaches up to 24.3 pm/V, making it highly efficient for frequency conversion and nonlinear optical applications.

BGSe Crystals are increasingly applied in areas such as biomedical spectroscopy, atmospheric sensing, and high-power mid-infrared optical parametric amplification (OPA) and oscillation (OPO) systems. With advanced optical clarity and damage resistance, BaGa4Se7 serves as one of the most promising materials for cutting-edge infrared applications requiring precise wavelength tuning and high-energy optical efficiency

General Applications and Examples

BaGa4Se7 Crystals excel in several specialized fields due to their exceptional nonlinear optical and transmission properties:

  1. Biomedical Spectroscopy:
    BGSe Crystals enable highly accurate spectroscopic measurements in mid-infrared wavelengths, ideal for applications such as bio-molecular fingerprinting and non-invasive diagnostics.
  2. Atmospheric Sensing and Remote Monitoring:
    With a wide transparency range and low absorption coefficients, BGSe Crystals are crucial for atmospheric gas monitoring, including CO and trace element detection, via laser-based technologies.
  3. OPO and OPA Systems:
    These crystals are essential in optical parametric oscillators and amplifiers for mid-infrared wavelength generation, enabling fine-tuning between 3–5 μm and 8–14 μm.
  4. Defense and Aerospace:
    Advanced IR laser systems utilizing BGSe Crystals support high-energy military applications, including lidar and infrared countermeasure systems.
  5. Advanced Research in Photonics:
    BGSe Crystals are pivotal in developing next-generation high-energy infrared optical devices, making them indispensable in academic and industrial R&D settings.

Chemical and Structural Properties

Property Value
Chemical Formula BaGa4Se7
Crystal Structure Orthorhombic
Lattice Parameters a = 11.224 Å, b = 12.457 Å, c = 7.145 Å
Density 4.77 g/cm³
Mohs Hardness 3.5
Melting Point 998°C
Thermal Conductivity 1.6 W/m·K (at 300 K)
Transparency Range 0.47–18 μm
Absorption Coefficient < 0.05 cm⁻¹ (at 1064 nm)
Damage Threshold > 1.2 J/cm² (at 1064 nm)

Optical and Nonlinear Optical Properties

Property Value
Transparency Range 0.47–18 μm
Refractive Indices (at 1064 nm) no = 2.671, ne = 2.847
Nonlinear Coefficient (pm/V) dmax = 24.3
Absorption Coefficient < 0.05 cm⁻¹ (at 1064 nm)
Laser Damage Threshold > 1.2 J/cm² (at 1064 nm)
Nonlinear Optical Efficiency 2–3 times that of AgGaS2

Standard Fabrication Specification

Specification Value
Orientation Accuracy ± 0.5°
Clear Aperture > 90%
Surface Quality (Scratch/Dig) 40-20
Flatness λ/8 at 633 nm
Parallelism < 30 arc sec
Perpendicularity < 10 arc min
Surface Flatness Tolerance ± 0.1 mm
Length Tolerance ± 0.1 mm (1–10 mm)
± 0.5 mm (> 10 mm)

Spectrum Transmission Curve

Spectrum transmission curves can be provided upon request, illustrating high efficiency across the 0.47–18 μm range.

Coating Specification

  • AR Coatings: Anti-reflective coatings available for 3–5 μm and 8–12 μm ranges.
  • Dual-Band Coatings: Customized coatings designed for specific laser applications.
  • Customization: Coatings for extended infrared applications are available upon request.
  • 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.
Face Dimensions (mm) Length (mm) Orientation (Theta/Phi) Coating Application Price (USD)
5 x 5 10 0°/0° AR @ 3–5 μm Mid-IR spectroscopy Request
10 x 10 15 0°/0° AR @ 8–12 μm OPO/OPA systems Request
Custom Custom Custom Custom Custom Request

POC-OC-122418-BaGa4Se7 Crystal

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