Pulse light source device and method for creating CEP stable fs laser pulses
A pulse light source device ( 100 ) for creating fs output laser pulses ( 1, 1.1, 1.2, 1.3 ) having CEP stability comprises a pulse source device ( 10 ) creating primary ps laser pulses, a first beam splitting device ( 13 ) splitting the primary ps laser pulses to first ps laser pulses ( 2.1 ) and second ps laser pulses ( 2.2 ), a pulse shortening device ( 20 ) creating sub-ps laser pulses ( 3 ) by shortening and spectrally broadening the first ps laser pulses ( 2.1 ), a primary supercontinuum generation device ( 30 ) creating primary fs laser pulses ( 4 ), a pulse stretcher device ( 40 ) creating stretched ps laser pulses ( 5, 5.1 ) by stretching the primary fs laser pulses ( 4 ), a optical parametric chirped-pulse amplification device ( 51 ) creating amplified ps laser pulses ( 6, 6.1 ) on the basis of the stretched ps laser pulses ( 5, 5.1 ) and the second ps laser pulses ( 2.2 ); a phase stabilization device ( 61 ) creating CEP stable ps laser pulses ( 7, 7.1 ) by difference frequency generation of the amplified ps laser pulses ( 6, 6.1 ) and reference laser pulses derived from the primary ps laser pulses ( 2 ) or the sub-ps laser pulses ( 3 ), a pulse compressor device ( 71 ) creating compressed fs laser pulses ( 8, 8.1 ) by compressing the CEP stable ps laser pulses ( 7, 7.1 ) output by the phase stabilization device ( 61 ), and a secondary supercontinuum generation device ( 81 ) creating fs output laser pulses as the fs output laser pulses ( 1, 1.1 ) to be obtained by spectrally broadening the compressed fs laser pulses ( 8, 8.1 ). Furthermore, a method of creating fs output laser pulses is described.
1. Pulse light source device, being configured for creating fs output laser pulses having carrier-envelope-phase (CEP) stability, comprising:
a pulse source device including a ps laser pulse source, which is arranged for creating primary ps laser pulses,
a first beam splitting device, which is arranged for splitting the primary ps laser pulses to first ps laser pulses and second ps laser pulses,
a pulse shortening device, which is arranged for creating first sub-ps laser pulses by shortening and spectrally broadening the first ps laser pulses using an optical nonlinear process,
a primary supercontinuum generation device, which is arranged for creating primary fs laser pulses by subjecting the first sub-ps laser pulses to a supercontinuum generation process,
a pulse stretcher device, which is arranged for creating stretched ps laser pulses by stretching the primary fs laser pulses,
a first optical parametric chirped-pulse amplification (OPCPA) device, which is arranged for creating first amplified ps laser pulses on the basis of the stretched ps laser pulses and the second ps laser pulses,
a first phase stabilization device, which is arranged for creating first CEP stable ps laser pulses by difference frequency generation of the first amplified ps laser pulses and reference laser pulses derived from the primary ps laser pulses or from the first sub-ps laser pulses,
a first pulse compressor device, which is arranged for creating first compressed fs laser pulses by compressing the first CEP stable ps laser pulses output by the first phase stabilization device, and
a first secondary supercontinuum generation device, which is arranged for creating first fs output laser pulses as the fs output laser pulses to be obtained by spectrally broadening the first compressed fs laser pulses.
2. Pulse light source device according to claim 1 , wherein
the pulse shortening device is arranged for creating the first sub-ps laser pulses with a pulse duration which is selected such that a peak power of the first sub-ps laser pulses is below a damage threshold of the primary supercontinuum generation device.
3. Pulse light source device according to claim 2 , wherein
the pulse shortening device is arranged for creating the first sub-ps laser pulses with a pulse duration in a range from 15 fs to 900 fs.
4. Pulse light source device according to claim 1 , wherein
the pulse shortening device includes a cross-polarized wave generation unit.
5. Pulse light source device according to claim 1 , wherein
the primary supercontinuum generation device includes a YAG crystal or a waveguide unit.
6. Pulse light source device according to claim 1 , wherein
the pulse stretcher device is arranged for creating stretched ps laser pulses with a duration matched to the duration of the primary ps laser pulses.
7. Pulse light source device according to claim 1 , wherein
the first beam splitting device which is arranged for splitting the primary ps laser pulses further to third ps laser pulses providing the reference laser pulses, and
the first phase stabilization device is arranged for creating the first CEP stable ps laser pulses by difference frequency generation of the first amplified ps laser pulses and the third ps laser pulses.
8. Pulse light source device according to claim 1 , further including
a second beam splitting device, which is arranged for splitting second sub-ps laser pulses from the first sub-ps laser pulses, the second sub-ps laser pulses providing the reference laser pulses, wherein
the first phase stabilization device is arranged for creating the first CEP stable ps laser pulses by difference frequency generation of the first amplified ps laser pulses and the second sub-ps laser pulses.
9. Pulse light source device according to claim 1 , further including
a third beam splitting device, which is arranged for spectrally selective splitting the stretched ps laser pulses and providing first stretched ps laser pulses having a first spectral intensity characteristic being included in the spectral supercontinuum characteristic of the primary fs laser pulses, wherein
the first OPCPA device is arranged for creating the first amplified ps laser pulses by amplifying the first stretched ps laser pulses on the basis of the second ps laser pulses.
10. Pulse light source device according to claim 9 , wherein
the third beam splitting device is arranged for additionally providing at least second stretched ps laser pulses having a spectral intensity characteristic being included in the spectral supercontinuum characteristic of the primary fs laser pulses and differing from the spectral intensity characteristic of the first stretched ps laser pulses, and
the pulse light source device further includes
at least one second OPCPA device, which is arranged for creating at least second amplified ps laser pulses by amplifying the second stretched ps laser pulses on the basis of the second ps laser pulses,
at least one second phase stabilization device, which is arranged for creating at least second CEP stable ps laser pulses by difference frequency generation of the second amplified ps laser pulses and the reference laser pulses,
at least one second pulse compressor device, which is arranged for creating at least second compressed fs laser pulses by compressing the second CEP stable ps laser pulses output by the at least one second phase stabilization device, and
at least one second secondary supercontinuum generation device, which is arranged for creating at least second fs output pulses contributing to the fs output laser pulses to be obtained by spectrally broadening the second compressed fs laser pulses.
11. Pulse light source device according to claim 10 , including
three spectral channels each with one of the OPCPA devices, phase stabilization devices, pulse compressor devices and secondary supercontinuum generation devices, wherein
the third beam splitting device is arranged for spectrally selective splitting the stretched ps laser pulses and providing the first, the second and third stretched ps laser pulses each with a specific spectral intensity characteristic differing from the spectral intensity characteristic of the other stretched ps laser pulses.
12. Pulse light source device according to claim 9 , including
a frequency shifting device, which is arranged for creating frequency shifted ps laser pulses from the second ps laser pulses and delivering the frequency shifted ps laser pulses to at least one of the first and at least one second OPCPA devices.
13. Pulse light source device according to claim 1 , further including
an amplification stage, which is arranged for amplifying the fs output laser pulses on the basis of a portion of the primary ps laser pulses.
14. Method of creating fs output laser pulses having carrier-envelope-phase (CEP) stability, comprising:
splitting primary ps laser pulses to first ps laser pulses and second ps laser pulses,
creating first sub-ps laser pulses by shortening and spectrally broadening the first ps laser pulses using an optical nonlinear process,
creating primary fs laser pulses by subjecting the first sub-ps laser pulses to a supercontinuum generation process,
creating stretched ps laser pulses by stretching the primary fs laser pulses, and
creating first amplified ps laser pulses on the basis of the stretched ps laser pulses and the second ps laser pulses,
creating first CEP stable ps laser pulses by difference frequency generation of the first amplified ps laser pulses and reference laser pulses derived from the primary ps laser pulses or from the sub-ps laser pulses,
creating first compressed fs laser pulses by compressing the first CEP stable ps laser pulses, and
creating first fs output laser pulses as the fs output laser pulses to be obtained by spectrally broadening the first compressed fs laser pulses.
15. Method according to claim 14 , wherein
the sub-ps laser pulses are created with a pulse duration which is selected such that a peak power of the sub-ps laser pulses is below a damage threshold of the supercontinuum generation process.
16. Method according to claim 15 , wherein
the sub-ps laser pulses are created with a pulse duration in a range from 15 fs to 900 fs.
17. Method according to claim 14 , wherein
the stretched ps laser pulses are created with a duration matched to the duration of the ps laser pulses.
18. Method according to claim 14 , including
splitting third ps laser pulses from the primary ps laser pulses providing the reference laser pulses, and
the first CEP stable ps laser pulses are created by difference frequency generation of the first amplified ps laser pulses and the third ps laser pulses.
19. Method according to claim 14 , including
splitting second sub-ps laser pulses from the first sub-ps laser pulses, the second sub-ps laser pulses providing the reference laser pulses, and
the first CEP stable ps laser pulses are created by difference frequency generation of the first amplified ps laser pulses and the second sub-ps laser pulses.
20. Method according to claim 14 , further including
spectrally selective splitting the stretched ps laser pulses and providing first stretched ps laser pulses having a first spectral intensity characteristic being included in the spectral supercontinuum characteristic of the primary fs laser pulses, wherein
the first amplified ps laser pulses are created by amplifying the first stretched ps laser pulses on the basis of the second ps laser pulses.
21. Method according to claim 20 , wherein
the step of spectrally selective splitting the stretched ps laser pulses additionally includes providing at least second stretched ps laser pulses having a spectral intensity characteristic being included in the spectral supercontinuum characteristic of the primary fs laser pulses and differing from the spectral intensity characteristic of the first stretched ps laser pulses, and
the method of creating fs output laser pulses further includes
creating at least second amplified ps laser pulses by amplifying the second stretched ps laser pulses on the basis of the second ps laser pulses,
creating at least second CEP stable ps laser pulses by difference frequency generation of the second amplified ps laser pulses and the reference laser pulses,
creating at least second compressed fs laser pulses by compressing the second CEP stable ps laser pulses, and
creating at least second fs output pulses contributing to the fs output laser pulses to be obtained by spectrally broadening the second compressed fs laser pulses.
22. Method according to claim 20 , including
creating frequency shifted ps laser pulses from the second ps laser pulses and delivering the frequency shifted ps laser pulses for at least one of the steps of creating the first amplified ps laser pulses and creating at least the second amplified ps laser pulses.
23. Method according to claim 14 , further including
coherently superimposing the fs output laser pulses.