Yb:KGd(WO4)2
Yb:KGW
- Ytterbium doped Potassium-Gadolinium Tungstate crystals - (Yb:KGd(WO4)2
or Yb:KGW) is an excellent laser gain material which has important advantages
over the widely used Nd3+ doped materials. Its broad spectral emission
band 1023-1060nm allows the generation of short (ps or fs) laser pulses.
Its wide absorption spectrum at 980 nm and high absorption of pump radiation
allow an efficient use of diode laser pumping. Compared with YAG used
as hosts for Yb3+, KGW has the advantage of larger absorption cross section,
which decreases the minimum pump intensity necessary to achieve transparency
in the quasi-two-level system of ytterbium.
Basic Properties
Crystal structure: monoclinic
Point group: C2/c
Cell Parameters: a = 8.09Å; b = 10.43 Å; c = 7.588 Å°
ß=94.4°
Refractive index: at 1067 nm nq = 2.033; np = 2.037; nm = 1.986
Mohs hardness: 5
Density, g/cm3: 7.27
Melting Point: 1075?
Thermal conductivity: at 373°K, W x cm-1 x °K-1 K[100] = 0.026;
K[010]= 0.038; K[001] = 0.034
Termal expansion coefficient: at 373°K a[100] = 4 x 10-6 x °K-1;
a[010]= 1.6 x 10-6 x °K-1; a [001]= 8.5 x 10-6 x °K-1
Lasing Wavelength: 1023-1060nm
Absorption band : 981nm(FWHM 3.7nm)
Fluorescent lifetime: 600 µs (5% doping)
Specifications of Yb:KGW
Orientation: [010]
Standard Dopant concentration: 5%atm
Maximum length: 50mm
Length tolerance: +1.0 / -0.0mm
Diameter tolerance: +/-0.1 mm
Parallelism: < 30\"
Perpendicularity: < 15'
Surface quality: 20/10 (MIL-PRF-13830B)
coating: AR-coated
