Name: | Laser Crystal Yb:KGW | Chemical Formula: | Potassium Gadolinium Tungastate |
---|---|---|---|
Crystal Structure: | Monoclinic Double Tungstates | Density: | 7.27 G/cm3 |
Transmission Range: | 0.35-5.5 M | Mohs Hardness: | 4 To 5 |
High Light: | nd yag laser rod,laser material |
Laser Crystal Yb:KGW
Yb3+: KGd(WO4)2 (Yb:KGW) is one of the most promising laser active materials. Yb:KGW crystal is expected to replace Nd:YAG crystal and Yb:YAG crystal in high power diode pumped laser system. Yb:KGW also has great potential for high power, short pulse time femtosecond lasers and their wide application.
The simple two-level electronic structure of the Yb ion avoids undesired loss processes such as upconversion, excited state absorption, and concentration quenching. Compared to the commonly used Nd:YAG crystal, Yb:KGW crystal has a much larger absorption bandwidth, 3 or 4 times longer emission lifetime in similar hosts with enhanced storage capacity, lower quantum defect and is more suitable for diode pumping than the traditional Nd-doped systems. The smaller Stokes shift reduces heating and increases the laser efficiency. In comparison with other Yb doped laser crystals such as Yb:YAG and Yb:YCOB crystals, Yb:KGW has a much higher (13-17 times) cross-section of absorption, lower quantum defect (~4%), a cross-section of emission that is 9 times higher than Yb: YCOB, and an emission band that is broader than Yb:YAG, a high nonlinear coefficient of refraction, and the highest slope efficiency (87%).
Chemical formula | potassium gadolinium tungastate |
Crystal structure | monoclinic double tungstates |
Density | 7.27 g/cm3 |
Transmission range | 0.35-5.5 m |
Mohs hardness | 4 to 5 |
Refractive indices at 1060 nm | ng = 2.037, np = 1.986, nm=2.033 |
Thermal conductivity | Ka=2.6 W/mK, Kb=3.8 W/mK, Kc=3.4 W/mK |
Thermal optical coefficient @1064 nm | dnp/dT=-15.7 * 10-6 K-1 |
dnm/dT=-11.8 * 10-6 K-1 | |
dng/dT=-17.3 * 10-6 K-1 | |
Thermal expansion | a=4X10-6 /°C |
b=3.6X10-6 /°C | |
c=8.5X10-6 /°C | |
Melting temperature | 1075 °C |
Absorbtion cross section | 1.2X10-19 cm2 |
Stimulated emission cross section (E| |a) | 2.6X10-20 cm2 |
Laser wavelength | 1023-1060 nm |
Lasing threshold | 35 mW |
Stark levels energy (in cm-1) of the 2F5/2 manifolds of Yb3+ @ 77 K | 10682, 10471, 10188 |
Stark levels energy (in cm-1) of the 2F7/2 manifolds of Yb3+ @ 77K | 535, 385, 163, 0 |
optical damage threshold, GW/cm2 | 20 |
Absorption peak wavelength, lpump, [nm] |
981.2 |
Absorption linewidth, Dlpump, [nm] |
3.7 |