Nd:YAG
Physical and Optical Properties
Chemical Formula................................................................................Nd:Y3 Al5 O12
Crystal Structure.............................................................................................. Cubic
Lattice Constants.............................................................................................12.01
Concentration............................................................................. ~ 1.2 x 1020 cm -3
Melting Point...............................................................................................1970 °C
Density...................................................................................................4.56 g/cm 3
Mohs Hardness....................................................................................................8.5
Refractive Index.................................................................................................1.82
Thermal Expansion Coefficient................................7.8 x 10 -6 /K [111], 0 - 250 °C
Thermal Conductivity...........................14 W/m /K @20 °C, 10.5 W /m /K @100 °C
Lasing Wavelength.....................................................................................1064 nm
Stimulated Emission Cross Section.................................................2.8x10 -19 cm -2
Relaxation Time of Terminal Lasing Level.........................................................30 ns
Radiative Lifetime..........................................................................................550 ms
Spontaneous Fluorescence...........................................................................230 ms
Loss Coefficient...................................................................0.003 cm -1 @ 1064 nm
Effective Emission Cross Section...................................................2.8 x 10 -19 cm 2
Pump Wavelength.....................................................................................807.5 nm
Absorption band at pump wavelength.............................................................1 nm
Linewidth......................................................................................................0.6 nm
Polarized Emission............................................................................... Unpolarized
Thermal Birefringence.......................................................................................High
Capabilities Include:
Nd dopant concentration.....0.5---1.2 atm% tolerance within 10% of concentration
Diameter...................................................................................................3 ~ 14mm
Length....................................................................................................1 ~ 160mm
Typical Specification and Tolerance:
Orientation....................................................<111> crystalline direction (+/-0.5°C)
Wavefront Distortion..................................................<λ/10 at 632.8nm for 3~7mm
......................................<λ/8 per inch at 632.8nm for >=7mm
Surface quality...............................better than 20/10 Scratch/Dig per MIL-O-1380A
Parallelism ....................................................................................< 10 arc seconds
Perpendicularity...............................................................................< 5 arc minutes
Surface flatness..........................................................................< λ/10 at 632.8nm
Clear aperture Central...................................................................................... 95%
Chamfer......................................................................................................0.15x45°
Damage threshold:
............................ over 15J/cm2 (rods without coating) over 700 MW/cm2 (coating)
Coatings ..............................................................................AR@1064nm,R < 0.1%;
.............................................AR@1064nm,R < 0.1%; HT@808nm,T > 95%;
...........................................HR@1064nm,R < 99.8%; HT@808nm,T > 95%;
.............................................................................HR@1064nm,R < 99.8%;
.................................................HT@808nm,T > 95%;HR@532nm,R > 99%;
