0000000001253898
AUTHOR
J. Kasparian
Experimental investigation of the optical Kerr effect at large laser intensity: impact on the propagation of a short and intense laser pulse
Talk given by O. Faucher; International audience
Higher-order Kerr terms allow ionization-free filamentation in gases
Talk given by J. Kasparian; International audience; Higher-order nonlinear indices, rather than plasma, provide the main defocusing contribution to filamentation in gases at 800 nm. Developing generalized Miller formulae, we discuss the generality of this as a function of the laser wavelength
Observation d'effets Kerr d'ordres élevés (HOKE) dans les gaz
Talk given by O. Faucher; National audience
Higher-order Kerr terms allow ionization-free filamentation in gases
International audience; We show that higher-order nonlinear indices (n4 , n6 , n8 , n10) provide the main defocusing contribution to self-channeling of ultrashort laser pulses in air and Argon at 800 nm, in contrast with the previously accepted mechanism of filamentation where plasma was considered as the dominant defocusing process. Their consideration allows to reproduce experimentally observed intensities and plasma densities in self-guided filaments.
Negative and positive Kerr nonlinearity of air calibrated with transient molecular alignment
Talk given by O. Faucher; International audience; Nonlinear electronic Kerr index of the major air constituents has been measured up to high order terms using transient molecular alignment as a reference. Sign reversal associated to negative nonlinearity is observed above a pulse intensity of 26 TW/cm^.2
High-order Kerr nonlinearity of air calibrated with transient molecular alignment
Talk given by O. Faucher; International audience; Nonlinear electronic Kerr index of the major air constituents has been measured up to high order terms using transient molecular alignment as a reference. Sign reversal associated to negative nonlinearity is observed above a pulse intensity of 26 TW/cm^2.