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Co:Spinel(Cobalt spinel)

Current Position: Home » Products » Co:Spinel(Cobalt spinel)
Co:Spinel(Cobalt spinel)

Co:spinel crystal, also known as cobalt spinel, with the chemical formula of Co2+: MgAl2O4, 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 at a safe wavelength of 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 1200-1600nm, indicating that 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 1520nm, which is most commonly used for eye safety laser.


  • 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


[1]  Denker B ,  Galagan B ,  Kisel V , et al. Passive shutters for Q-switching continuously diode-pumped Er-glass laser[M].  2005.
[2] K, Izumi, S, et al. Optical properties of 3d transition-metal-doped MgAl2O4 spinels[J]. Physical Review B, 2007, 76(7):75111-75111.
[3]  Nataf L , F Rodríguez,  Valiente R . Pressure-induced Co2+ photoluminescence quenching in MgAl2O4[J]. Physical review. B, Condensed matter, 2012, 86(12):4995-5013.
[4]  Yumashev K V ,  Denisov I A ,  Kuleshov N V . Passive Q-switching of 1.34-/spl mu/m neodymium laser using Co/sup 2+/:LiGa/sub 5/O/sub 8/ and Co/sup 2+/:MgAl/sub 2/O/sub 4/[C]// Conference Digest. 2000 Conference on Lasers and Electro-Optics Europe (Cat. No.00TH8505). IEEE, 2000.
[5]  Lin H Y ,  Sun D ,  Copner N , et al. Nd:GYSGG laser at 1331.6 nm passively Q-switched by a Co:MgAl2O4 crystal[J]. Optical Materials, 2017, 69:250-253.
[6]  Bajor A L ,  Chmielewski M ,  Diduszko R , et al. Czochralski growth and characterization of MgAl2O4 single crystals[J]. Journal of Crystal Growth, 2014, 401(sep.1):844-848.
[7] Javed, Ahmad, Maria, et al. Effect of Co2+ substitution on MgAl2O4 studied by infrared reflectance spectroscopy[J]. Optik International Journal for Light & Electron Optics, 2017.
[8]  Belghachem N ,  Mlynczak J ,  Kopczynski K , et al. Thermal analysis of a diffusion bonded Er3+,Yb3+:glass/Co2+: MgAl2O4 microchip lasers[J]. Optical Materials, 2016, 60:546-551.
[9] Nabil, Belghachem, Jaroslaw, et al. Comparison of laser generation in thermally bonded and unbonded Er3+,Yb3+:glass/Co2+:MgAl2O4 microchip lasers[J]. Optical Materials, 2015.
[10]  Duan X L ,  Song C F ,  Wu Y C , et al. Preparation and optical properties of nanoscale MgAl 2O 4 powders doped with Co 2+ ions[J]. Journal of Non-Crystalline Solids, 2008, 354(29):3516-3519.
[11]  Yumashev K V ,  Denisov I A ,  Posnov N N , et al. Nonlinear absorption properties of Co2+:MgAl2O4 crystal[J]. Applied Physics B, 2000, 70(2):179-184.
[12]  Kanwal K ,  Ismail B ,  Rajani K S , et al. Effect of Co2+ Ions Doping on the Structural and Optical Properties of Magnesium Aluminate[J]. Journal of Electronic Materials, 2017.
[13]  Ryabtsev G L ,  Bezyazychnaya T V ,  Bogdanovich M V , et al. Optimized diode-pumped passive Q-switched ytterbium–erbium glass laser[J]. Applied Physics B, 2012, 108(2):283-288.
[14]  Tolstik N A ,  Troshin A E ,  Kurilchik S V , et al. Spectroscopy, continuous-wave and Q-switched diode-pumped laser operation of Er3+,Yb3+:YVO4 crystal[J]. Applied Physics B, 2007, 86(2):275-278.
[15]  Mlynczak J ,  Belghachem N . Monolithic thermally bonded Er3+, Yb3+:glass/Co2+:MgAl2O4 microchip lasers[J]. Optics Communications, 2015, 356(4):166-169.
[16]  Duan X L ,  Yuan D R ,  Cheng X F , et al. Absorption and photoluminescence characteristics of Co 2+:MgAl 2O 4 nanocrystals embedded in sol–gel derived SiO 2-based glass[J]. Optical Materials, 2004, 25(1):65-69.
[17]  Nemec M ,  Jelinkova H ,  Sulc J , et al. Passive Q-switching at 1645 nm of Er:YAG laser with Co:MALO saturable absorber[C]// Quantum Electronics Conference & Lasers & Electro-optics. IEEE, 2012.
[18]  Bhardwaj A ,  Agrawal L ,  Pal S , et al. Optimization of passively Q -switched Er:Yb:Cr:phosphate glass laser: theoretical analysis and experimental results[J]. Applied Physics B, 2007, 86(2):293-301.
[19]  Kalashnikov V L ,  Shcherbitsky V G ,  Kuleshov N V , et al. Pulse energy optimization of passively Q-switched flash-lamp pumped Er:glass laser[J]. Applied Physics B, 2002, 75(1):35-39.

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


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