Sales engineer
Arminas Butkus +370 5 219 4884
Tm, Ho:KYW crystals
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Tm, Ho:KYW crystals

Main features


  • Large and broad polarized absorption and emission bands
  • Efficient energy transfer Tm3+ → Ho3+
  • High dopant concentration with low concentration-quenching
  • Custom crystals available upon request


Application examples


  • 2 μm lasers for for remote sensing (LIDAR technology), metrology and
    medical applications
  • Pump source of mid-IR optical parametric oscillators (OPOs)
Request custom
  • Description
  • Properties
  • Standard specifications

Ho3+ ions are generally characterized by higher emission cross-sections and longer upper laser level lifetimes compared to Tm3+ counterparts. These features are especially desirable for low-threshold and efficient laser operation. It is recognised, however, that because Ho3+ does not possess strong absorption lines that are well matched to the outputs of commercially available laser diodes, the co-doping of Ho3+ with Tm3+ ions is normally chosen to enable efficient operation across 2 μm spectral region through energy transfer routes in the Tm–Ho system. Tm, Ho:KYW crystals are characterized by large and broad polarized absorption and emission bands, efficient energy transfer Tm3+ → Ho3+.

Spectroscopic and thermo-mechanical properties
Absorption peak wavelength 802 nm
Absorption cross-section at peak 7.6×10-20 cm2
Absorption bandwidth at peak wavelength ~4 nm
Laser wavelength 2060 nm
Lifetime of 5I7 energy level 1.8 ms
Emission cross-section @2056 nm 4.7×10-20 cm2
Refractive index @1040nm ng=2.05, nm=2.01, np=1.97
Crystal structure monoclinic
Density 6.5 g/cm3
Mohs hardness 4-5
Thermal conductivity ~3.3 Wm-1K-1
dn/dT dnm/dT=-9.2×10-6 K-1
Thermal expansion coefficient αp=1.83×10-6 K-1, αm=10.29×10-6 K-1,
αg=15.94×10-6 K-1
Typical doping level 5 at.% [Tm]
0.5 at.% [Ho]
Tm, Ho:KYW crystals
Orientation Ng-cut
Clear aperture >90%
Face dimensions tolerance +0/-0,1 mm
Length tolerance ±0,1 mm
Parallelism error <10 arcsec
Perpendicularity error <10 arcmin
Protective chamfers <0,1 mm at 45˚
Surface quality 10-5 S-D
Surface flatness <λ/[email protected],8 nm
Coatings R<0,5% @802 nm + R<0,15% @2000-2100 on both faces
LIDT >10 J/cm2@2060 nm, 10 ns
Mount Unmounted
Order your item
Face dimensions Length End faces Doping Coatings SKU price quantity
3x3 mm
2 mm
Right-angle cut
Tm 5%, Ho 0,5%
AR/[email protected] nm+2000-2100 nm
600 €
3x3 mm
2 mm
Brewster cut
Tm 5% Ho 0,5%
460 €