High Power ND: Yvo4 Laser Crystal

• Customization: Available
• After-sales Service: 12 Months
• Warranty: 12 Months
• Customized: Customized
• Standard Component: Standard Component
• Type: Laser Crystals
• Crystal Structure: Zircon Tetragonal, Space Group D4h-I4/AMD
• Doping Concentration: 0.07%~3%
• Clear Aperture: >95%
• Transport Package: Shockproof Carton
• Origin: China

Product Description

Introduction

Neodymium Doped Yttrium Orthovanadate (Nd:YVO₄) is the most efficient laser host crystal for diode pumping among the current commercial laser crystals, especially, for low to middle power density. This is mainly for its absorption and emission features surpassing Nd:YAG. Pumped by laser diodes, Nd:YVO₄ crystal has been incorporated with high NLO coefficient crystals (LBO, BBO, or KTP) to frequency-shift the output from the near infrared to green, blue, or even UV. This incorporation to construct all solid state lasers is an ideal laser tool that can cover the most widespread applications of lasers, including machining, material processing, spectroscopy, wafer inspection, light displays, medical diagnostics, laser printing, and data storage, etc. It has been shown that Nd:YVO₄ based diode pumped solid state lasers are rapidly occupying the markets traditionally dominated by water-cooled ion lasers and lamp-pumped lasers, especially when compact design and single-longitudinal-mode output are required.

Technical Specifications	Details
Doping Concentration	0.07%~3%
Concentration Tolerance	±0.05% (for at% < 1%), ±0.1% (for at% ≥ 1%)
Crystal Orientation	A-cut/C-cut ± 0.5°
Dimensional Tolerances	±0.1 mm
Flatness	λ/10 at 632.8 nm
Wavefront Distortion	λ/10 at 632.8 nm
Surface Quality	10/5 per MIL-O-13830B
Parallelism	10 arcseconds
Perpendicularity	10 arcminutes
Chamfering	<0.1 mm at 45°
Edge Chipping	<0.1 mm
Clear Aperture	>95%
Coating	AR/HR/PR per customer specifications
Laser Damage Threshold of Coating	7.5 J/cm² at 1064 nm, TEM00, 10 ns, 10 Hz

Nd:YVO₄'s advantages over Nd:YAG

• As high as about five times larger absorption efficient over a wide pumping bandwidth around 808 nm (therefore, the dependency on pumping wavelength is much lower and a strong tendency to the single mode output)
• As large as three times larger stimulated emission cross-section at the lasing wavelength of 1064 nm.
• Lower lasing threshold and higher slope efficiency.
• As a uniaxial crystal with large birefringence, the emission is only linearly polarized

Laser Properties of Nd:YVO₄

1. One most attractive character of Nd:YVO₄ is, compared with Nd:YAG, its 5 times larger absorption coefficient in a broader absorption bandwidth around the 808 nm peak pump wavelength, which just matches the standard of high power laser diodes currently available. This means a smaller crystal that could be used for the laser, leading to a more compact laser system. For a given output power, this also means a lower power level at which the laser diode operates, thus extending the lifetime of the expensive laser diode. The broader absorption bandwidth of Nd:YVO₄ which may reaches 2.4 to 6.3 times that of Nd:YAG. Besides more efficient pumping, it also means a broader range of selection of diode specifications. This will be helpful to laser system makers for wider tolerance for lower cost choice.

2. Nd:YVO₄ crystal has larger stimulated emission cross-section, both at 1064 nm and 1342 nm. When a-axis cut Nd:YVO₄ crystal lasing at 1064 nm, it is about 4 times higher than that of Nd:YAG, while at 1340 nm the stimulated cross-section is 18 times larger, which leads to a CW operation completely outperforming Nd:YAG at 1320 nm. These make Nd:YVO₄ laser be easy to maintain a strong single line emission at the two wavelengths.

3. Another important character of Nd:YVO₄ lasers is, because it is an uniaxial rather than a high symmetry of cubic as Nd:YAG, it only emits a linearly polarized laser, thus avoiding undesired birefringent effects on the frequency conversion. Although the lifetime of Nd:YVO₄ is about 2.7 times shorter than that of Nd:YAG, its slope efficiency can be still quite high for a proper design of laser cavity, because of its high pump quantum efficiency.

The major laser properties of Nd:YVO₄ vs Nd:YAG are listed in Table 2 below, including stimulated emission cross-sections(σ), absorption coefficient (α), fluorescent lifetime (τ), absorption length (L_α), threshold power (P_th) and pump quantum efficiency (η_S).

Table  Laser Properties of Nd:YVO₄ vs Nd:YAG

Laser Crystal	Doping (at.%)	σ (×10^-19cm^2)	α (cm^-1)	τ (μs)	Lα (mm)	Pth (mW)	ηS (%)
Nd:YVO4(a-cut)	1.0	25	31.2	90	0.32	30	52
	2.0	25	72.4	50	0.14	78	48.6
Nd:YVO4(c-cut)	1.1	7	9.2	90		231	45.5
Nd:YAG	0.85	6	7.1	230	1.41	115	38.6