What are femtosecond lasers and why do we use them?

Femtosecond lasers emit optical pulses with a pulse duration in the domain of femtoseconds (1 fs = 10-15 s) typically ranging between a few femtoseconds to hundreds of femtoseconds. So, femtosecond lasers focus the energy on a very short time scale within a single laser pulse. That leads to high peak powers that cannot be achieved by continuous wave lasers, for instance.

Femtosecond pulses can be generated by different kinds of laser technologies, commonly solid state lasers (Ti:sapphire lasers) or more recently, fiber lasers. In general fiber lasers offer a lot of advantages compared to solid state lasers.

Ultrafast fiber lasers have revolutionized the field of photonics. One of the main advantages of using ultrafast femtosecond fiber lasers is the high peak power they offer which make them ideal for a wide range of applications where peak power is especially important. These applications include precision micromachining, medical procedures, and especially biomedical imaging such as multiphoton microscopy.

Due to the waveguide effect of optical fibers the laser systems have very good thermal and vibrational stability and can produce nearly diffraction limited beam profiles. In general fiber lasers offer a low cost of ownership and they are essentially maintenance-free.

In addition, due to the amorphous structure of the glass, the gain bandwidth of rare earth doped optical fibers is much more wideband compared to solid state doped materials. Therefore, fiber lasers can offer a wide wavelength tunablity. In addition, a large gain bandwidth also enables the generation of ultrashort optical pulses. Typical ultrafast pulse durations are determined by the optical gain bandwidth, so the wider the bandwidth the shorter the pulse that can be generated in theory.

Thanks to an innovative laser design with sophisticated control of dispersion and non-linear effects, the VALO Femtosecond Series lasers offer ultra-short pulses with pulse durations below 50 fs from a compact, robust and turn-key system.

With outstandingly high pulse peak power levels and computer controlled group velocity dispersion pre-compensation, the VALO ultrafast femtosecond fiber lasers are ideal for multiphoton imaging, neuroscience, optogenetics and advanced spectroscopy applications.

Our VALO Femtosecond Series lasers have an even higher optical bandwidth than the gain bandwidth due to a perfect interaction of linear and nonlinear effects. Due to this unique design, the VALO Femtosecond Series lasers can generate clean ultrafast optical pulses with pulse durations below 50 fs at unmatched power levels.

• <50 fs pulse duration
• Up to 2 W output power
• Very low noise
• Integrated pre-compensation dispersion module