Co:Spinel Crystal (Cobalt spinel)

Co:Spinel Crystal (Cobalt spinel)

Co:spinel crystal, also known as cobalt spinel, with the chemical formula of Co2+: MgAl2O4. It is a relatively excellent Q-switched crystal product.

Cobalt spinel is a saturable absorber that can be used for passive Q-switching of solid-state lasers in human eyes. Its safe wavelength is 1.5 μm.

Cobalt-doped magnesium aluminate spinel (Co2+: MgAl2O3) can produce short nanosecond pulses at eye-safe wavelength of 1.5 μm.

The peak power near m is very suitable for telemetry applications. The utility model has the advantages of high absorption section, long service life, uniform cobalt distribution, absorption bandwidth, etc.

The absorption spectrum of Co2+ doped MgAl2O4 shows a wide absorption band in the wavelength range of 1200-1600 nm. That indicat Co2+ ions replace tetrahedrally coordinated Mg2+ ions in MgAl2O4 lattice.

Passive Q-switching of solid-state lasers with solid-state saturable absorbers is a very attractive Q-switching technology. Because it allows the development of compact and low-cost nano and sub nanosecond pulsed laser sources.

In industrial applications, due to 1.5 μm laser radiation has high eye safety, so this wavelength has been widely concerned.

Other advantages of this wavelength are the high transparency of atmospheric and fused silica waveguides and the availability of sensitive room temperature photodetectors (Ge and InGaAs photodiodes). This makes 1.5 μm laser is very suitable for rangefinder, environmental sensing, telecommunications, surgery and so on.

The absorption peak of Co:spinel is close to 1520 nm, which is most commonly used for eye safety laser.

The Features Of Co:spinel Crystal:

  • Stimulate the long life
  • High absorption section
  • Q switch high constant
  • Wide absorption band
  • Uniform distribution of cobalt
  • Rare stimulates the absorption

Physical and Chemical Properties

Chemical FormulaCo2+:MgAl2O4
Crystal StructureCubic
Lattice Constant8.07Å
Density3.62 g/cm3
Melting Point2105°C
Refractive Indexn=1.6948 @1.54 μm
Thermal Conductivity/((W·cm-1·K-1 @ 25°C)0.033W
Thermal Expansion/(10-6 /°C @ 25°C)1.046
Specific Heat/(J·g-1·K-15.9
Mohs Hardness8.2
Extinction Ratio25dB
Orientation[100] or [111] < ±0.5°
Optical Density0.1-0.9
Damage Threshold>500 MW/cm2
Co2+Doping Concentration0.01-0.3 atm%

Material Specifications

Concentration(0.05~0.35) wt%
Absorption Coefficient 0 ~ 7 cm-1
Ground State Absorption Cross SectionGSA(E-19 cm22.8(±0.4)@1340nm
Excited State Absorption Cross Section ESA(E-20 cm22.0(±0.6)@1340nm
Ground State Absorption Cross Section GSA(E-20 cm23.5(±0.4)@1540nm
Excited State Absorption Cross Section ESAA(E-20 cm21.0(±0.6)@1540nm
Working Wavelength1200 – 1600 nm
Final ConfigurationFlat/Flat
Quality factor(FOM)100~300

Absorption Emission Spectrum

Co spinel Q switched crystal absorption spectrum 1 CRYLINKCo spinel Q-switched crystal absorption spectrum 2 CRYLINK
Co spinel Q-switched crystal emission spectrum CRYLINK


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Related product(s) with Co:Spinel:

Er-Yb-Glass+co-spinel-CRYLINK Er glass-CRYLINK
Er,Yb:glass+Co:spinel Erbium:glass(Er,Yb:Glass)
Glass+Er,Ybglass-CRYLINK Glass+Er,Ybglass+Cospinel-CRYLINK
Glass+Er,Yb:glass+Glass Glass+Er,Yb:glass+Co:spinel
Co:Spinel(Cobalt spinel)

Cobalt spinel (co:spinel), chemical formula Co2+:MgAl2O4, is an excellent saturable absorber and very efficient passive Q-switch with a high absorption cross section that emits 1.2 µm – 1.6 µm lasers.

Product Brand: CRYLINK

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