Nd:YAG Laser Crystal

22 May 2019

Description

Nd: YAG one of the mature developed laser crystals which is obtained by doping Nd ion into YAG crystal. The absorption bandwidth of Nd:YAG laser crystal are 730-760 nm and 790-820 nm, and usually pumped by flashtube or laser diode. The typical laser emission peak is 1064 nm, the wavelength of 946 nm, 1120 nm, 1320 nm and 1440 nm lasers can be emitted too through some measures, Q-switch and lock mode are adapted to obtain laser with different wavelength (532 nm, 266 nm, 213 nm etc.) and pulse width (10-25 ns) respectively, which makes the huge application in biophysics, medicine, military, machine, scientific research and architecture etc.. Commonly, the high concentration doped crystal is applied into pulse laser and the low concentration doped one is usually used in continuous wave output.

Parameter

Material and Specifications

Nd Concentration Tolerance (atm%)	0.1- 2.5(+/-0.1)atm%
Orientation	[001] or [110] or [111] <±0.5°
Parallelism	10〞
Perpendicularity	5ˊ
Surface Quality	10-5(MIL-O-13830A)
Wavefront Distortion	λ/4@632 nm
Surface Flatness	λ/8@632 nm
Clear Aperture	>95 %
Chamfer	<0.2×45°
Length Tolerance	+0.5/-0mm
Thickness/Diameter Tolerance	±0.05 mm
Maximum Dimensions	dia (3~12.7)×(3~150) mm
Damage Threshold	>750 MW/cm²@1064 nm 10 ns 10 Hz
Chips
Extinction Ratio	>30 dB(depends on actual sizes )
Barrel Finish	400 grit

Physical and Chemical Properties

Crystal Structure	cubic – la3d
Lattice Constants	12.01 Å
Density	4.56 g/cm³
Melting Point	1950 °C
Thermal Conductivity/(W·m-1·K-1@25°C)	0.14 W
Specific Heat/(J·g^-1·K^-1)	0.59
Rupture Stress	1.3-2.6*10³ kg/cm²
Thermal Expansion /（10^-6·K^-1@25°C ）	[100] Orientation–8.2
	[110] Orientation–7.7
	[111] Orientation–7.8
Hardness (Mohs)	8.5
Young`s Modulus/GPa	317
Shear Modulus/Gpa	54.66
Extinction Ratio	25 dB
Poisson Ratio	0.25

Optical and Spectral Properties

Laser Transition	⁴F_3/2→> ⁴I_11/2
Photon Energy	1.86×10^-19J
Laser Transition Wavelength, λ_l (nm)	1064
Pump Transition Wavelength, λ_p (nm)	808
Pump Transition Bandwidth, Δλ_p (nm)	<4
Laser Transition Bandwidth, Δλ_l (nm)	~0.6
Pump Transition Peak Cross Section, σ_p (E^-20cm²)	6.7
Laser Transition Peak Cross Section, σ_l (E^-20cm²)	28
Pump Transition Saturation Intensity, φ_p (kW/cm²)	12
Laser Transition Saturation Intensity, φ_l (kW/cm²)	2.6
Laser Transition Saturation Fluence, Γ_l,sat (J/cm²)	0.6
Minimum Pump Intensity, I_min (kW/cm²)	~0
Upper Laser Manifold Lifetime, τ(msec)	0.26
Quantum Defect Fraction	0.24
Fractional Heat Generation	0.37
Refractive Index	1.8197 @1.064 µm
Fluorescence Lifetime	230 µs