Solid-State Photonics Group

Fields of work

• Crystal and laser design for power scaling of diode pumped solid-state lasers
• Fiber based laser systems with variable pulse shaping
• Fiber amplification of narrow-linewidth laser sources

Crystal and laser design

In Nd:YAG solid-state lasers with high average output power the use of laser rods with differently doped segments and a pump wavelength of 885 nm results in an efficient optimization of laser conversion efficiency and thermal management. In this way an output power of more than 750 W with an optical-to-optical conversion efficiency of 58% can be extracted from a compact laser head (50 cm x 20 cm).

Laser systems based on Nd:YVO4 crystals enable an efficient and direct amplification of various laser sources. Pulsed or narrow-linewidth continuous-wave lasers can be scaled to output powers in excess of 100 W with excellent beam quality. Special crystal designs and pump wavelengths around 885 nm can also be applied in Nd:YVO4 laser systems to reduce thermal effects that limit a further power scaling.

Fiber based laser source with variable pulse shaping

The project PULSAR (Pulsed laser system with adaptable pulse parameters) funded in the framework of BMBF initiative INLAS concentrates on the development of different pulsed laser sources with pico- and nanosecond pulses. Laser oscillators with low average output power are being amplified with fiber based amplifiers to power levels attractive to industrial micromachining applications. Decoupling the laser oscillator from the amplifier unit enables a maximum variability of pulse parameters with respect to pulse duration, shape and repetition rate and results in a fast and novel process optimization. http://www.ot-inlas.de/inlas/pulsar/

Fiber amplification of narrow-linewidth laser sources

The development of high-power, narrow-linewidth laser sources for world-wide scientific projects on gravitational-wave detectors has been advanced in the department for laser development since many years. In the field of fiber based amplifiers the main scientific focus is on nonlinear optical processes such as stimulated Brillouin scattering (SBS) that limit the extractable output power. Concepts for fiber amplifier systems with extremely high power and excellent beam quality for a future generation of detectors are being developed.