title: Spectral Fraunhofer regime: time-to-frequency conversion by the action of a single time lens on an optical pulse.
abstract: We analyze a new regime in the interaction between an optical pulse and a time lens (spectral Fraunhofer regime), where the input pulse amplitude is mapped from the time domain into the frequency domain (time-to-frequency conversion). Here we derive in detail the conditions for achieving time-to-frequency conversion with a single time lens (i.e., for entering the spectral Fraunhofer regime) as well as the expressions governing this operation. Our theoretical findings are demonstrated both numerically and experimentally. A comparative study between the proposed single-time-lens configuration and the conventional dispersion + time-lens configuration for time-to-frequency conversion is also conducted. Time-to-frequency conversion with a single time lens can be used for applications similar to those previously proposed for the conventional time-to-frequency converters, e.g., high-resolution measurement of fast optical temporal waveforms. Moreover, our results also indicate that the spectral Fraunhofer regime provides additional capabilities for controlling and processing optical pulses.
authors.affiliation: Institut National de la Recherche Scientifique--Energie, Matériaux et Télécommunications, 800 de la Gauchetière Ouest, Suite 6900, Montréal, Québec H5A 1K6, Canada. azana@inrs-emt.uquebec.ca
authors.forename: José
authors.initials: J
authors.lastname: Azaña
authors.forename: Naum K
authors.initials: NK
authors.lastname: Berger
authors.forename: Boris
authors.initials: B
authors.lastname: Levit
authors.forename: Baruch
authors.initials: B
authors.lastname: Fischer