We show that the propagation of a femtosecond laser pulse inside a photonic structure can be directly visualized and tracked as it propagates using a time-resolved photon scanning tunneling microscope. From the time-dependent and phase-sensitive measurements, both the group velocity and the phase velocity are unambiguously and simultaneously determined. It is expected that this technique will find applications in the investigation of the local dynamic behavior of photonic crystals and integrated optical circuits.
Bibliographical notePublisher: American Association for the Advancement of Science
Other: First two named authors contributed equally to paper