High Resolution Multiphoton Spectroscopy by a Tunable Free-Electron-Laser Light

Žitnik, M.; Mihelič, A.; Bučar, K.; Kavčič, M.; Rubensson, J. E.; Svanquist, M.; Söderström, J.; Feifel, R.; Såthe, C.; Ovcharenko, Y.; Lyamayev, V.; Mazza, T.; Meyer, M.; Simon, M.; Journel, L.; Lüning, J.; Plekan, O.; Coreno, M.; Devetta, M.; Di Fraia, Michele; Finetti, P.; Richter, R.; Prince, K.  . C.; Callegari, C.

doi:10.1103/PhysRevLett.113.193201

Seeded free electron lasers theoretically have the intensity, tunability, and resolution required for multiphoton spectroscopy of atomic and molecular species. Using the seeded free electron laser FERMI and a novel detection scheme, we have revealed the two-photon excitation spectra of dipole-forbidden doubly excited states in helium. The spectral profiles of the lowest (−1,0)+1 Se1 and (0,1)0 De1 resonances display energy shifts in the meV range that depend on the pulse intensity. The results are explained by an effective two-level model based on calculated Rabi frequencies and decay rates.

Titolo:	High Resolution Multiphoton Spectroscopy by a Tunable Free-Electron-Laser Light
Autori:	M. Žitnik A. Mihelič K. Bučar M. Kavčič J. E. Rubensson M. Svanquist J. Söderström R. Feifel C. Såthe Y. Ovcharenko V. Lyamayev T. Mazza M. Meyer M. Simon L. Journel J. Lüning O. Plekan M. Coreno M. Devetta DI FRAIA, MICHELE P. Finetti R. Richter K. .C. Prince C. Callegari mostra contributor esterni nascondi contributor esterni
Data di pubblicazione:	2014
Rivista:	PHYSICAL REVIEW LETTERS
Abstract:	Seeded free electron lasers theoretically have the intensity, tunability, and resolution required for multiphoton spectroscopy of atomic and molecular species. Using the seeded free electron laser FERMI and a novel detection scheme, we have revealed the two-photon excitation spectra of dipole-forbidden doubly excited states in helium. The spectral profiles of the lowest (−1,0)+1 Se1 and (0,1)0 De1 resonances display energy shifts in the meV range that depend on the pulse intensity. The results are explained by an effective two-level model based on calculated Rabi frequencies and decay rates.
Handle:	http://hdl.handle.net/11368/2820123
Digital Object Identifier (DOI):	http://dx.doi.org/10.1103/PhysRevLett.113.193201
Appare nelle tipologie:	1.1 Articolo in Rivista

File in questo prodotto:

Non ci sono file associati a questo prodotto.

Utilizza questo identificativo per citare o creare un link a questo documento:
http://hdl.handle.net/11368/2820123

Citazioni

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

ArTS Archivio della ricerca di Trieste

File in questo prodotto: