We report measurements demonstrating the concept of the free-electron laser (FEL) superradiant cascade. Radiation (lambda(rad) = 200 nm) at the second harmonic of a short, intense seed laser pulse (lambda(seed) = 400 nm) was generated by the cascaded FEL scheme at the transition between the modulator and radiator undulator sections. The superradiance of the ultrashort pulse is confirmed by detailed measurements of the resulting spectral structure, the intensity level of the produced harmonics, and the trend of the energy growth along the undulator. These results are compared to numerical particle simulations using the FEL code GENESIS 1.3 and show a satisfactory agreement. DOI: 10.1103/PhysRevLett.110.044801
Superradiant Cascade in a Seeded Free-Electron Laser / L., Giannessi; M., Bellaveglia; E., Chiadroni; A., Cianchi; M. E., Couprie; M. D., Franco; G. D., Pirro; M., Ferrario; G., Gatti; M., Labat; G., Marcus; Mostacci, Andrea; A., Petralia; V., Petrillo; M., Quattromini; J. V., Rau; S., Spampinati; V., Surrenti. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - ELETTRONICO. - 110:4(2013), p. 044801. [10.1103/physrevlett.110.044801]
Superradiant Cascade in a Seeded Free-Electron Laser
E. Chiadroni;MOSTACCI, Andrea;
2013
Abstract
We report measurements demonstrating the concept of the free-electron laser (FEL) superradiant cascade. Radiation (lambda(rad) = 200 nm) at the second harmonic of a short, intense seed laser pulse (lambda(seed) = 400 nm) was generated by the cascaded FEL scheme at the transition between the modulator and radiator undulator sections. The superradiance of the ultrashort pulse is confirmed by detailed measurements of the resulting spectral structure, the intensity level of the produced harmonics, and the trend of the energy growth along the undulator. These results are compared to numerical particle simulations using the FEL code GENESIS 1.3 and show a satisfactory agreement. DOI: 10.1103/PhysRevLett.110.044801I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.