A laser cavity with its own gain medium in which a Pockels cell captures one pulse from a seed oscillator, holds it for tens of round trips while it grows from nanojoules to millijoules, then switches it out. Regens are the standard first stage of femtosecond CPA systems at kHz rates. Getting Pockels cell timing, build-up time and seed matching right is everyday regen work.
Regen build-up looks fine on the photodiode, 18 round trips, so the energy drop has to be after the dump.
Also heard as
- regenerative amplifier
Related terms
CPA
Chirped Pulse Amplification: stretching a short pulse before amplifying it, then recompressing it afterwards.
Pockels cell
An electro-optic crystal that changes a beam's polarization when high voltage is applied, used as a fast optical switch.
Seed
The low-power laser whose output is amplified in a MOPA or amplifier chain, setting its timing and spectrum.
Rep rate
Clipped form of repetition rate: how many pulses per second a pulsed laser emits.