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Résumé |
The concept of space-time duality, known since the 1960s, is attracting attention in recent years in the context of temporal imaging. In this talk I first review this topic and discuss how a time lens can be used for optical signal processing in a variety of applications.
I then focus on my group’s work on the temporal analog of reflection and refraction of optical pulses inside a dispersive medium with a temporal boundary across which the refractive index changes. As an optical pulse approaches this boundary, it splits into two parts that propagate at different speeds because of their widely different spectra. An analog of total internal reflection also occurs when the refractive index change at the boundary is large enough. This phenomenon can be used to make a temporal waveguide that confines optical pulses within a temporal window. I also discuss how the nonlinear phenomenon of cross-phase modulation can be used for making such a temporal waveguide by employing a pump-probe configuration.
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