1. Introduction
This article explains Yb:YAG crystal applications in industrial ultrafast lasers. This crystal is playing an increasingly important role in the field of industrial lasers due to its excellent physical properties. Yb:YAG not only inherits the superior physical properties and stable chemical performance of the YAG matrix material but also exhibits good laser performance due to its longer upper laser level lifetime.
In industrial applications, Yb:YAG lasers are widely used in material processing, medical equipment manufacturing, and scientific research due to their high power, high repetition rate, and high beam quality. The following are several Yb:YAG crystal applications in the industrial sector:
2. Yb:YAG crystal applications Ⅰ: 1030nm Infrared Lasers
Among industrial lasers, 1030nm wavelength Yb:YAG lasers are favored for their high power and high beam quality. These lasers can provide high-energy laser output, suitable for high-precision and demanding processing tasks. For example, the AOFEMTO series of industrial high-power femtosecond lasers provided by Innolight have a super short laser pulse width of <800fs and customizable spot roundness of over 95%. These lasers support trigger and level trigger control, and SYNC synchronous output functions. With reliable pulse stability (<2%), they can achieve up to 50W of infrared output, making them ideal for high-precision and demanding precision processing.
Figure 1. Application of Yb:YAG crystal in 1030nm laser
The GS-FIR150 series of 150W infrared femtosecond lasers from Guoshen Laser, with their cold processing and high-precision advantages, are widely used in sapphire cutting, glass QR code marking, stainless steel drilling/cutting, and other fields. This series of lasers provides a pulse width of <600fs in the near-infrared band, with output powers of 100W/150W and single-pulse energy of 300uJ/500uJ, ensuring high efficiency and precision in the processing process.
3. Yb:YAG crystal applications Ⅱ: 515nm Green Lasers
Yb:YAG lasers at 515nm wavelength are achieved through second harmonic generation and are important in the fields of fine processing and microprocessing, especially in applications requiring shorter wavelengths to improve processing precision and depth. For example, the TruMicro 5000 series of picosecond and femtosecond lasers from Germany’s TRUMPF can provide laser output at 515nm wavelength, with pulses of less than 10ps and single-pulse energy up to 500μJ. These lasers can rapidly vaporize materials with almost no heat impact, making them suitable for processing semiconductor materials, metals, dielectrics, plastics, and glass.
Currently, mainstream 515nm and 343nm femtosecond lasers are based on pump modules composed of slab Yb:YAG crystals and heat sink units combined with frequency doubling modules.
Figure 2. Slab Yb:YAG pump module
4. Yb:YAG crystal applications Ⅲ: 343nm Ultraviolet Lasers
Yb:YAG lasers at 343nm wavelength are achieved through third harmonic conversion and are important in the fields of microelectronics and semiconductor manufacturing, especially in applications requiring extreme ultraviolet light for fine processing. For example, the PHAROS series of femtosecond lasers from Lithuania’s LIGHT CONVERSION can provide up to fifth harmonic or tunable extension, including 343nm ultraviolet output. These lasers, with their high energy and high average power, as well as tunable pulse duration (100fs – 20ps) and high repetition rates (1Hz – 1MHz), are suitable for industrial applications related to semiconductor manufacturing.
Figure 3. Yb:YAG raw crystal
5. Yb:YAG crystal applications Ⅳ: OPCPA Tunable Light Sources
Optical parametric chirped pulse amplification (OPCPA) technology is an advanced technique for generating ultra-short pulses and broadband spectra. Yb:YAG lasers, due to their high power and high repetition rate, are ideal pump sources for OPCPA systems. For example, the ORIGAMI XPS series of lasers from Denmark’s NKT Photonics is an all-in-one single-box microjoule femtosecond laser that provides excellent energy and pointing stability, making it highly efficient for on-board monitoring and diagnostic functions. This laser has an average power of >5W and pulse energy of <70μJ, making it suitable for OPCPA applications requiring high energy and high stability.
The ultrafast, wide-tunable lasers manufactured by Spain’s Radiantis integrate pump lasers and OPOs, providing a complete wide-tunable laser solution suitable for various scientific and technical applications. These lasers offer femtosecond or picosecond pulses and have a wide range of wavelength tuning capabilities, making them suitable for material nonlinear characterization, time-resolved experiments, nonlinear spectroscopy such as coherent anti-Stokes Raman spectroscopy (CARS), and nonlinear microscopy such as multiphoton microscopy.
Figure 4. Finished Yb:YAG crystal
6. Conclusion
In summary, Yb:YAG crystals, due to their unique physical properties, are increasingly widely used in the industrial field, especially in the design and implementation of high-power, high-repetition-rate, and high-beam-quality laser systems. With the continuous advancement of technology, Yb:YAG crystals are expected to play an even more important role in future industrial applications.
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