Titanium-sapphire lasers can step aside. According to its manufacturer, Spectra-Physics, the ytterbium-tungstate (Yb:KGW) Eclipse high-power femtosecond amplified laser offers the simplest and most rugged architecture as well as the lowest cost of ownership of any high-power femtosecond amplifier system.
While Ti-sapphire amplifiers need two intracavity frequency-doubled green-pump lasers, laser diodes can directly pump Yb:KGW. The Eclipse outputs 4 W at 1048 nm. It operates at pulse repetition rates up to 7 kHz and generates pulse widths of less than 500 fs. An optional frequency doubler module enables the Eclipse to deliver 1.5 W of output power at 524 nm.
Its modular design includes two directly diode-pumped monolithic building blocks: a low-power seed oscillator and a regenerative amplifier. Two fiber-coupled single-emitter laser diodes pump the oscillator, and two de-rated diode bars pump the amplifier module. The four ProLite pump diodes are located in the rack-mounted system electronics and fiber-coupled to the laser head for a simple laser-head architecture and easy maintenance.
Saturable Bragg Reflector technology passively mode-locks the seed oscillator, enhancing reliability. The mode-locking is self-starting, and it never experiences dropouts. The compact laser head measures 44 by 26 by 11 inches. No external cooling water is necessary for the system.
All of the Eclipse's parameters are accessible through a user-friendly GUI on a laptop. This simplifies system integration into complex setups and operation while preserving flexibility. Also, users can select a pulse repetition rate from single shot to 7 kHz. Users can even create bursts of pulses, which is an advantage in industrial applications.
Applications include femtosecond precision materials processing and ultrafast research, such as pump-probe experiments and nonlinear optics. At 524 nm, the Eclipse's high-power beam can pump one or more optical parametric amplifiers for tunability between ultraviolet (less than 325 nm) and infrared (greater than 10,000 nm).
Spectra-Physics
www.spectra-physics.com
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