Abstract: Provided are a method and an apparatus for measuring the spectral intensity and phase of a light pulse having an arbitrary time duration. The apparatus includes: a nonlinear mixing means for generating a signal light pulse expressed by the following Formula (? denotes an operator representing general nonlinear mixing, and ? denotes a coefficient which is proportional to a nonlinear susceptibility in the nonlinear mixing) by nonlinearly mixing a reference light pulse having an electric field Er(t??) delayed by an optical delay means and a measurement target light pulse having an electric field E0(t); and Er(t??)+?Er(t??)?E0(t) an imaging spectrum device for spectrally splitting the signal light pulse and outputting a Fourier transform signal expressed by the following Formula (F denotes a symbol indicating Fourier transform, * denotes a complex conjugate, and R denotes a symbol indicating a real part), |F[Er(t??)]|2+|?F[Er(t??)?E0(t)]|2+2R{?F[Er(t??)]*·F[Er(t??)?E0(t)]}.

Abstract: Provided are a method and an apparatus for measuring the spectral intensity and phase of a light pulse having an arbitrary time duration. The apparatus includes: a nonlinear mixing means for generating a signal light pulse expressed by the following Formula (? denotes an operator representing general nonlinear mixing, and ? denotes a coefficient which is proportional to a nonlinear susceptibility in the nonlinear mixing) by nonlinearly mixing a reference light pulse having an electric field Er(t??) delayed by an optical delay means and a measurement target light pulse having an electric field E0(t); and Er(t??)+?Er(t??)?E0(t) an imaging spectrum device for spectrally splitting the signal light pulse and outputting a Fourier transform signal expressed by the following Formula (F denotes a symbol indicating Fourier transform, * denotes a complex conjugate, and R denotes a symbol indicating a real part), |F[Er(t??)]|2+|?F[Er(t??)?E0(t)]|2+2R{?F[Er(t??)]*·F[Er(t??)?E0(t)]}.

Abstract: Method and device for the generation of a comb of stabilized frequency lines and/or a train of ultrashort laser pulses for stabilization of the position of the carrier wave with respect to the amplitude envelope of few cycles laser pulses. Interference between spectral components generated by means of difference frequency generation and self phase modulation in one and the same non-linear crystal (4) allows detecting and stabilizing the temporal evolution of the carrier-envelope offset (CEO) phase. The described technique improves dramatically the accuracy of the stabilization and has very small insertion losses.

Abstract: Method and device for the generation of a comb of stabilized frequency lines and/or a train of ultrashort laser pulses for stabilization of the position of the carrier wave with respect to the amplitude envelope of few cycles laser pulses. Interference between spectral components generated by means of difference frequency generation and self phase modulation in one and the same non-linear crystal (4) allows detecting and stabilizing the temporal evolution of the carrier-envelope offset (CEO) phase. The described technique improves dramatically the accuracy of the stabilization and has very small insertion losses.