FEL2011 - List of Authors (Labat, M.)

Paper

Title

Page

High Harmonics from Gas, a Suitable Source for Seeding FEL from the Vacuum-ultraviolet to Soft X-ray Region

9

G. Lambert, J. Gautier, V. Malka, A. Sardinha, S. Sebban, F. Tissandier, B. Vodungbo, P. Zeitoun
LOA, Palaiseau, France
B. Carré, D. Garzella
CEA/DSM/DRECAM/SPAM, Gif-sur-Yvette, France
O.V. Chubar, M.-E. Couprie, M. Labat
SOLEIL, Gif-sur-Yvette, France
M. Fajardo
IPFN, Lisbon, Portugal
T. Hara
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
C.P. Hauri
Paul Scherrer Institut, Villigen, Switzerland
H. Kitamura, T. Shintake
RIKEN/SPring-8, Hyogo, Japan
J. Lüning
CCPMR, Paris, France
Y.T. Tanaka
JASRI/SPring-8, Hyogo-ken, Japan
T. Tanikawa
PhLAM/CERCLA, Villeneuve d'Ascq Cedex, France

FEL have been recently evolving very fast in the extreme-ultraviolet to soft X-ray region. Once seeded with high harmonics generated in gas, these light sources deliver amplified emissions with properties which are, for most of them, directly linked to the injected harmonic beam, e.g. the ultrashort pulse duration for FEL and the high temporal and spatial degree of coherence. Since the last two years the developments of techniques for improving the harmonic properties for seeding FEL lead to major results on tunability, intensity, repetition rate and polarization. Actually harmonics are nowadays used for numbers of applications, before limited to FEL facility. Also, FEL based on harmonic seeding can benefit from the natural synchronization between the FEL, the harmonic and the laser used for generation, which makes it a perfect candidate for pump-probe experiment with fs resolution.

Slides MOOBI2 [1.782 MB]

MOPB16

New Tunable DUV Light Source for Seeding Free-electron Lasers

38

N.Y. Joly, W. Chang, P. Hölzer, J. Nold, P.St.J. Russell, J.C. Travers
Max Planck Institute for the Science of Light, Erlangen, Germany
M.-E. Couprie, M. Labat
SOLEIL, Gif-sur-Yvette, France

Seeding of single-pass free-electron lasers is a promising approach for improving the temporal coherence compared to self-amplified spontaneous emission [1], at the same time reducing the saturation length and reinforcing the harmonic level. Convention lasers or harmonics generated in gas are usually used as coherent seeds [1]. However such sources require complicated set-up and have limited tuneability. Here, we suggest the use of a newly discovered and efficient source of UV light, continuously tunable from 120 nm to 320 nm. The extremely compact and simple set-up consists of 20 cm of hollow-core photonic crystal fibre filled with a noble gas at variable pressure up to a few tens of bar and pumped by ~1 μJ 30 fs pulses at 800 nm [2]. The process relies on a favourable sequence of linear and nonlinear effects: low pressure-tunable dispersion, pulse compression due to a combination of self-phase-modulation and anomalous dispersion, self-steepening and dispersive wave generation. Tunable diffraction-limited DUV pulses of ~50 nJ and fs duration are generated. Seeding of FEL is discussed.
[1] G. Lambert et al., Nature Physics 4, 296-300 (2008)
[2] N. Joly et al., accepted in PRL

TUPA06

Seeding Schemes on the French FEL Project LUNEX5

198

C. Evain, F. Briquez, M.-E. Couprie, M. Labat, A. Loulergue
SOLEIL, Gif-sur-Yvette, France
V. Malka
LOA, Palaiseau, France

LUNEX5 is a single pass FEL project producing coherent synchrotron radiation with, in a first step, an electron bunch accelerated in conventional RF cavities up to 300 MeV. It is planned to work in a seeded configuration where the longitudinal coherence of the emitted light is improved and the gain length reduced, compared to the SASE configuration (Self-Amplified Spontaneous Emission). Two seeding schemes are considered: High order Harmonic in Gas seeding and EEHG scheme (Echo Enabled Harmonic Generation). Preliminary simulation results indicate that these two schemes permit to reach the saturation below a wavelength of 7 nm, and with less undulator periods for the EEHG scheme. Finally, the feasibility of plasma acceleration based FEL will also be investigated on this facility.

WEOB3

Seeding Experiments at SPARC

M. Labat, F. Briquez, M.-E. Couprie
SOLEIL, Gif-sur-Yvette, France
D. Alesini, M. Bellaveglia, M. Castellano, E. Chiadroni, G. Di Pirro, A. Drago, M. Ferrario, L. Ficcadenti, A. Gallo, G. Gatti, A. Ghigo, E. Pace, B. Spataro, C. Vaccarezza
INFN/LNF, Frascati (Roma), Italy
A. Bacci, V. Petrillo, A.R. Rossi, L. Serafini
Istituto Nazionale di Fisica Nucleare, Milano, Italy
M. Bougeard, B. Carré, D. Garzella
CEA/DSM/DRECAM/SPAM, Gif-sur-Yvette, France
A. Cianchi
Università di Roma II Tor Vergata, Roma, Italy
F. Ciocci, G. Dattoli, M. Del Franco, L. Giannessi, A. Petralia, M. Quattromini, C. Ronsivalle, E. Sabia, I.P. Spassovsky, V. Surrenti
ENEA C.R. Frascati, Frascati (Roma), Italy
L. Cultrera
CLASSE, Ithaca, New York, USA
D. Filippetto
LBNL, Berkeley, California, USA
F. Frassetto, L. P. Poletto
LUXOR, Padova, Italy
G. Lambert
LOA, Palaiseau, France
G. Marcus, J.B. Rosenzweig
UCLA, Los Angeles, California, USA
M. Migliorati, A. Mostacci, L. Palumbo
Rome University La Sapienza, Roma, Italy
J.V. Rau
ISM-CNR, Rome, Italy
M. Serluca
INFN-Roma, Roma, Italy
C. Vicario
PSI, Villigen PSI, Switzerland

The SPARC FEL amplifier has been configured as a single stage HGHG FEL with a modulator and a radiator operating at the second harmonic. The HGHG cascade has been seeded with harmonics generated in a gas cell where a Ti:Sa laser pulse of 120 fs of duration is converted into higher harmonics. The cascaded FEL configuration obtained by tuning the undulator gaps has been studied by varying the number of modulators and radiators to optimize the conversion efficiency. The process of harmonic generation in a free electron laser operating in superradiant regime has been also analysed. Harmonic generation is expected to be efficient because of the quasi steady-state distribution of the e-beam phase space predicted in this regime. Harmonics up to the 11th have been experimentally observed.

Slides WEOB3 [5.198 MB]

TUPA09

LUNEX5: A FEL Project Towards the Fifth Generation in France

208

M.-E. Couprie, C. Benabderrahmane, F. Briquez, J. Daillant, J.-C. Denard, C. Evain, P. Eymard, F. Ferrari, J.-M. Filhol, M. Labat, A. Loulergue, P. Marchand, C. Miron, P. Morin, F. Polack
SOLEIL, Gif-sur-Yvette, France
S. Bielawski, C. Szwaj
PhLAM/CERCLA, Villeneuve d'Ascq Cedex, France
B. Carré
CEA/DSM/DRECAM/SPAM, Gif-sur-Yvette, France
N. Delerue, R. Roux, A. Variola
LAL, Orsay, France
G. Lambert, V. Malka, A. Rousse
LOA, Palaiseau, France
J. Lüning
CCPMR, Paris, France

LUNEX5 (free electron Laser Using a New accelerator for the Exploitation of X-ray radiation of 5th generation) aims at investigating the production of short intense and coherent pulses in the soft X rays region (down to 7 nm on the fifth harmonic). It comprises a free electron laser in the seeded configuration (High order Harmonic in Gas seeding and Echo Enable Harmonic Generation) using a conventional linear accelerator of 300 MeV. The FEL beamline including 15 m of in vacuum (potentially cryogenic undulators) of 15 and 30 mm period is designed so as to also accommodate a Laser Wake Field Accelerator (LWFA) ranging from 0.3 to 1 GeV, relying on electron beam parameters produced and accelerated by either the 60 TW laser of LOA or by the 10 PW APOLLON laser of ILE. After the completion and testing of the FEL with the conventional accelerator installed inside the SOLEIL booster inner area, the FEL line can be transported to a LWFA. A laser could alternatively be implemented at SOLEIL for starting testing the principles of a fifth generation light source.

WEPA14

Effect of a Quasiperiodic Undulator on FEL Radiation

352

F. Briquez, C. Benabderrahmane, M.-E. Couprie, C. Evain, M. Labat
SOLEIL, Gif-sur-Yvette, France

The operation of conventional undulators results from an interference scheme in order to generate radiation of a fundamental wavelength and its harmonics. Whereas these harmonics are in most of the cases useful to reach higher energies, it is profitable in specific configurations to shift or reduce them, for instance to limit power on optics or to distinguish between one or two photon process in user experiments. This can be performed by so-called quasi-periodic undulators in which the periodicity of the magnetic field is destructed. In this case, the field amplitude is reduced on a few positions among the axis, inducing a destruction of the interference scheme. Such undulators are commonly used to generate spontaneous emission in synchrotron radiation facilities but could also be installed in Free Electron Lasers. The emitted radiation of the quasi-periodic undulator is compared with the usual configuration one, in the case of LUNEX5. Simulations using GENESIS code are described and results are discussed.

Paper	Title	Page
MOOBI2	High Harmonics from Gas, a Suitable Source for Seeding FEL from the Vacuum-ultraviolet to Soft X-ray Region	9
	G. Lambert, J. Gautier, V. Malka, A. Sardinha, S. Sebban, F. Tissandier, B. Vodungbo, P. Zeitoun LOA, Palaiseau, France B. Carré, D. Garzella CEA/DSM/DRECAM/SPAM, Gif-sur-Yvette, France O.V. Chubar, M.-E. Couprie, M. Labat SOLEIL, Gif-sur-Yvette, France M. Fajardo IPFN, Lisbon, Portugal T. Hara RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan C.P. Hauri Paul Scherrer Institut, Villigen, Switzerland H. Kitamura, T. Shintake RIKEN/SPring-8, Hyogo, Japan J. Lüning CCPMR, Paris, France Y.T. Tanaka JASRI/SPring-8, Hyogo-ken, Japan T. Tanikawa PhLAM/CERCLA, Villeneuve d'Ascq Cedex, France
	FEL have been recently evolving very fast in the extreme-ultraviolet to soft X-ray region. Once seeded with high harmonics generated in gas, these light sources deliver amplified emissions with properties which are, for most of them, directly linked to the injected harmonic beam, e.g. the ultrashort pulse duration for FEL and the high temporal and spatial degree of coherence. Since the last two years the developments of techniques for improving the harmonic properties for seeding FEL lead to major results on tunability, intensity, repetition rate and polarization. Actually harmonics are nowadays used for numbers of applications, before limited to FEL facility. Also, FEL based on harmonic seeding can benefit from the natural synchronization between the FEL, the harmonic and the laser used for generation, which makes it a perfect candidate for pump-probe experiment with fs resolution.
	Slides MOOBI2 [1.782 MB]

MOPB16	New Tunable DUV Light Source for Seeding Free-electron Lasers	38
	N.Y. Joly, W. Chang, P. Hölzer, J. Nold, P.St.J. Russell, J.C. Travers Max Planck Institute for the Science of Light, Erlangen, Germany M.-E. Couprie, M. Labat SOLEIL, Gif-sur-Yvette, France
	Seeding of single-pass free-electron lasers is a promising approach for improving the temporal coherence compared to self-amplified spontaneous emission [1], at the same time reducing the saturation length and reinforcing the harmonic level. Convention lasers or harmonics generated in gas are usually used as coherent seeds [1]. However such sources require complicated set-up and have limited tuneability. Here, we suggest the use of a newly discovered and efficient source of UV light, continuously tunable from 120 nm to 320 nm. The extremely compact and simple set-up consists of 20 cm of hollow-core photonic crystal fibre filled with a noble gas at variable pressure up to a few tens of bar and pumped by ~1 μJ 30 fs pulses at 800 nm [2]. The process relies on a favourable sequence of linear and nonlinear effects: low pressure-tunable dispersion, pulse compression due to a combination of self-phase-modulation and anomalous dispersion, self-steepening and dispersive wave generation. Tunable diffraction-limited DUV pulses of ~50 nJ and fs duration are generated. Seeding of FEL is discussed. [1] G. Lambert et al., Nature Physics 4, 296-300 (2008) [2] N. Joly et al., accepted in PRL

TUPA06	Seeding Schemes on the French FEL Project LUNEX5	198
	C. Evain, F. Briquez, M.-E. Couprie, M. Labat, A. Loulergue SOLEIL, Gif-sur-Yvette, France V. Malka LOA, Palaiseau, France
	LUNEX5 is a single pass FEL project producing coherent synchrotron radiation with, in a first step, an electron bunch accelerated in conventional RF cavities up to 300 MeV. It is planned to work in a seeded configuration where the longitudinal coherence of the emitted light is improved and the gain length reduced, compared to the SASE configuration (Self-Amplified Spontaneous Emission). Two seeding schemes are considered: High order Harmonic in Gas seeding and EEHG scheme (Echo Enabled Harmonic Generation). Preliminary simulation results indicate that these two schemes permit to reach the saturation below a wavelength of 7 nm, and with less undulator periods for the EEHG scheme. Finally, the feasibility of plasma acceleration based FEL will also be investigated on this facility.

WEOB3	Seeding Experiments at SPARC
	M. Labat, F. Briquez, M.-E. Couprie SOLEIL, Gif-sur-Yvette, France D. Alesini, M. Bellaveglia, M. Castellano, E. Chiadroni, G. Di Pirro, A. Drago, M. Ferrario, L. Ficcadenti, A. Gallo, G. Gatti, A. Ghigo, E. Pace, B. Spataro, C. Vaccarezza INFN/LNF, Frascati (Roma), Italy A. Bacci, V. Petrillo, A.R. Rossi, L. Serafini Istituto Nazionale di Fisica Nucleare, Milano, Italy M. Bougeard, B. Carré, D. Garzella CEA/DSM/DRECAM/SPAM, Gif-sur-Yvette, France A. Cianchi Università di Roma II Tor Vergata, Roma, Italy F. Ciocci, G. Dattoli, M. Del Franco, L. Giannessi, A. Petralia, M. Quattromini, C. Ronsivalle, E. Sabia, I.P. Spassovsky, V. Surrenti ENEA C.R. Frascati, Frascati (Roma), Italy L. Cultrera CLASSE, Ithaca, New York, USA D. Filippetto LBNL, Berkeley, California, USA F. Frassetto, L. P. Poletto LUXOR, Padova, Italy G. Lambert LOA, Palaiseau, France G. Marcus, J.B. Rosenzweig UCLA, Los Angeles, California, USA M. Migliorati, A. Mostacci, L. Palumbo Rome University La Sapienza, Roma, Italy J.V. Rau ISM-CNR, Rome, Italy M. Serluca INFN-Roma, Roma, Italy C. Vicario PSI, Villigen PSI, Switzerland
	The SPARC FEL amplifier has been configured as a single stage HGHG FEL with a modulator and a radiator operating at the second harmonic. The HGHG cascade has been seeded with harmonics generated in a gas cell where a Ti:Sa laser pulse of 120 fs of duration is converted into higher harmonics. The cascaded FEL configuration obtained by tuning the undulator gaps has been studied by varying the number of modulators and radiators to optimize the conversion efficiency. The process of harmonic generation in a free electron laser operating in superradiant regime has been also analysed. Harmonic generation is expected to be efficient because of the quasi steady-state distribution of the e-beam phase space predicted in this regime. Harmonics up to the 11th have been experimentally observed.
	Slides WEOB3 [5.198 MB]

TUPA09	LUNEX5: A FEL Project Towards the Fifth Generation in France	208
	M.-E. Couprie, C. Benabderrahmane, F. Briquez, J. Daillant, J.-C. Denard, C. Evain, P. Eymard, F. Ferrari, J.-M. Filhol, M. Labat, A. Loulergue, P. Marchand, C. Miron, P. Morin, F. Polack SOLEIL, Gif-sur-Yvette, France S. Bielawski, C. Szwaj PhLAM/CERCLA, Villeneuve d'Ascq Cedex, France B. Carré CEA/DSM/DRECAM/SPAM, Gif-sur-Yvette, France N. Delerue, R. Roux, A. Variola LAL, Orsay, France G. Lambert, V. Malka, A. Rousse LOA, Palaiseau, France J. Lüning CCPMR, Paris, France
	LUNEX5 (free electron Laser Using a New accelerator for the Exploitation of X-ray radiation of 5th generation) aims at investigating the production of short intense and coherent pulses in the soft X rays region (down to 7 nm on the fifth harmonic). It comprises a free electron laser in the seeded configuration (High order Harmonic in Gas seeding and Echo Enable Harmonic Generation) using a conventional linear accelerator of 300 MeV. The FEL beamline including 15 m of in vacuum (potentially cryogenic undulators) of 15 and 30 mm period is designed so as to also accommodate a Laser Wake Field Accelerator (LWFA) ranging from 0.3 to 1 GeV, relying on electron beam parameters produced and accelerated by either the 60 TW laser of LOA or by the 10 PW APOLLON laser of ILE. After the completion and testing of the FEL with the conventional accelerator installed inside the SOLEIL booster inner area, the FEL line can be transported to a LWFA. A laser could alternatively be implemented at SOLEIL for starting testing the principles of a fifth generation light source.

WEPA14	Effect of a Quasiperiodic Undulator on FEL Radiation	352
	F. Briquez, C. Benabderrahmane, M.-E. Couprie, C. Evain, M. Labat SOLEIL, Gif-sur-Yvette, France
	The operation of conventional undulators results from an interference scheme in order to generate radiation of a fundamental wavelength and its harmonics. Whereas these harmonics are in most of the cases useful to reach higher energies, it is profitable in specific configurations to shift or reduce them, for instance to limit power on optics or to distinguish between one or two photon process in user experiments. This can be performed by so-called quasi-periodic undulators in which the periodicity of the magnetic field is destructed. In this case, the field amplitude is reduced on a few positions among the axis, inducing a destruction of the interference scheme. Such undulators are commonly used to generate spontaneous emission in synchrotron radiation facilities but could also be installed in Free Electron Lasers. The emitted radiation of the quasi-periodic undulator is compared with the usual configuration one, in the case of LUNEX5. Simulations using GENESIS code are described and results are discussed.