Patent ID: 8310749

Claim:
Source of high-power ultrashort light pulses comprising: a first laser pump source ( 1 ) adapted to deliver a first pump light flow ( 12 ), a mode-locked laser oscillator ( 2 ) adapted to receive said first pump light flow ( 12 ) and to deliver ultrashort input light pulses ( 3 ), said input light pulses having an input-pulse spectrum S 1 with a bandwidth B 1 , a second laser pump source ( 4 ) adapted to deliver a second pump light flow ( 5 ), a waveguide ( 6 ) adapted to receive said second pump light flow ( 5 ) and to amplify the input light pulses ( 3 ) in a non-linear regime in order to introduce spectral phases in the input light pulses ( 3 ), generating ultrashort amplified light pulses ( 7 ), having an asymmetrical amplified-pulse spectrum S 2 with a bandwidth B 2 , a compressor ( 8 ) adapted to time-compress the amplified light pulses ( 7 ), said compressor ( 8 ) generating predetermined spectral phases in the amplified light pulses ( 7 ), characterized in that: the waveguide ( 6 ) consists of a means adapted to compensate for the predetermined spectral phases generated at least by the compressor ( 8 ), the second laser pump source ( 4 ) being adapted to deliver a second pump light flow ( 5 ) having a power P L such that the spectral phases generated by the waveguide ( 6 ) are opposed or quasi-opposed to the predetermined spectral phases generated by the compressor ( 8 ), in order to generate, at the output of the compressor ( 8 ), compressed ultrashort light pulses ( 9 ) with spectral phase, the waveguide ( 6 ) being adapted to amplify the input light pulses ( 3 ) in a non-linear regime, said amplifying optical fiber having a length greater than the critical length Lc beyond which the bandwidth B 2 of the amplified-pulse spectrum S 2 is the same or almost the same as the bandwidth B 3 of the gain spectrum S 3 of the waveguide ( 6 ), and in that the amplifying optical fiber ( 6 ) comprises a first portion of fiber having a critical length Lc over which the input light pulses ( 3 ) are transmitted in a parabolic regime, and a second portion of fiber over which the input light pulses ( 3 ) are transmitted in a non-linear regime.