Neodymium Doped Yttrium Orthvanadate (Nd:YVO₄)

Neodymium doped yttrium vanadate (Nd:YVO4) is a very efficient laser host crystal which is available for diode laser pumped solid state lasers. It is an excellent crystal for a high power, stable and cost effective solid state laser sources due to a high laser induced damage threshold, good mechanical and optical properties, a large stimulated emission cross-section at lasing wavelength, a high absorption coefficient and a wide absorption bandwidth at pumping wavelength. Recent developments have shown that Nd:YVO4 can produce powerful and stable IR, green, blue lasers with the design of Nd:YVO4 and frequency doubling crystals.

Features:  

• Low lasing threshold and high slope efficiency
• Large stimulated emission cross-section at lasing wavelength
• High absorption over a wide pumping wavelength bandwidth
• Polarized laser source generation due to optical birefringence

Absorption Curves of Different Doping Concentrations:  

Due to a high absorption coefficient at the pumping wavelength 808nm, a short crystal around 1mm is preferred and a compact laser can be constructed. Nd:YVO4 has a wide absorption bandwidth, which does not require a stringent wavelength control and diode laser selection. Figure 1 & 2 show absorption curves at two different doping concentrations.

Fluorescence Spectra Curves:  

Figure 3 & 4 show fluorescence spectra curves of a-cut Nd:YVO4 with a doping concentration 1.1%. Figure 3 & 4 are for polarization state parallel and perpendicular to z axis respectively.

Laser Properties:  

The Nd:YVO4 crystal has large stimulated emission cross-sections at both 1064nm and 1342nm. The stimulated emission cross-section of an a-axis cut Nd:YVO4 crystal at 1064nm is about 4 times higher than that of the Nd:YAG crystal. Although the lifetime of Nd:YVO4 is about 2.7 times shorter than that of Nd:YAG, the slope efficiency of a Nd:YVO4 laser can be very high if the laser cavity is properly designed due to its high pump quantum efficiency . Table 1 lists the major laser properties of Nd:YVO4 in comparison with those of Nd:YAG. Table 2 lists the Nd:YVO4 crystal properties.