Picophotonics lasers utilize in-house developed semiconductor based absorber technology (SESAM) for passive Q-switching. This enables significant pulse width reduction, while keeping the simple and robust microchip laser architecture. The signal can be further amplified in a simple master oscillator – power amplifier (MOPA) configuration. This will not affect the spectral or temporal properties of the laser.

SESAM chips in gelbox

In comparison to pulsed diode lasers and mode-locked fiber lasers, our technology can offer a unique combination of output parameters:

  • From low repetition rate (10-100 kHz), avoiding the need for an external pulse picker in micro-machining applications, to MHz level for applications in imaging.
  • High peak power (1-3 kW) directly from the seed laser, both at 1064 nm and 1535 nm.
  • Upto 0.1 µJ pulse energy at 1064 nm and 3 µJ at 1535 nm, directly from the seed laser.
  • Single-frequency output with narrow spectral width Δλ<0.15 nm
  • Short pulse width, Δt<100 ps at 1064 nm and ns range at 1535 nm.
Chip handled with tweezers

The narrow spectral width and high peak power enable efficient single-pass conversion to 532 nm, 355 nm and 266 nm, simply by cascading appropriate stages of frequency-conversion.

Other wavelengths, such as 573 nm, 620 nm, 1240 nm, 1485 nm, 1852 nm, etc. can also be obtained by pumping a Raman-laser with the sub 100 ps pulses. The Raman laser can be formed simply of a thin monolithic piece of diamond with appropriate coatings. (Vol. 25, No. 24 | 27 Nov 2017 | OPTICS EXPRESS 3036, and Sub-100 ps monolithic diamond Raman laser emitting at 573 nm. IEEE Photonics Technology Letters, 30(11), 981-984. DOI: 10.1109/LPT.2018.2806183). Both nonlinear frequency-conversion and Raman conversion will shorten the pulse width.