Femtosecond Two-Photon Laser Photoelectron Microscopy

Abstract

It is shown that high-resolution photoelectron images (with a resolution of up to 3 nm for ultrasharp silicon tips) can be obtained for practically all materials when irradiating tips made of these materials by pulses of the second harmonic of a femtosecond Ti:sapphire laser. In addition to the images, absolute values of the two-photon external photoelectric effect for these tips also can be measured using this method. The first experimental realization of this two-photon femtosecond laser projection photoelectron microscope is presented, and corresponding data for silicon, diamond, and calcium fluoride tips are analyzed.

Femtosecond Imaging of Surface Plasmon Dynamics in a Nanostructured Silver Film

“…Imaging electrons with a PEEM makes possible the imaging of SPs modes with spatial resolution beyond the limits of conventional far-field optics . The possibility of high spatio-temporal resolution imaging through a combination of ultrafast laser and electron optic methods has been demonstrated before, though no actual time-resolved measurements have been performed. , In this letter we present a movie of the spatio-temporal evolution of SP fields with a 50-nm spatial resolution taken at with 330-as/frame (see Supporting Information). This unprecedented temporal resolution is achieved by scanning the delay between 10 fs duration pump−probe pulse with 50-as temporal precision.…”

Femtochemistry

“…Light pulses generate electrons, which can be detected with high spatial resolution. This approach has been realised by Secatskii et al 169 The researchers used very sharp silicone pins at the end of which femtosecond pulses were focused. These pulses induced two-photon emission of electrons, which was detected by a microscope.…”