posted on 2023-06-08, 17:52authored byMostafa Shalaby, Justyna Fabianska, Marco Peccianti, Yavuz Ozturk, Francois Vidal, Hans Sigg, Roberto Morandotti, Thomas Feurer
Terahertz fields can be dramatically enhanced as they propagate through nanometer-sized slits. The enhancement is mediated by a significant accumulation of the induced surface charges on the surrounding metal. This enhancement is shown here to be dynamically modulated while the nanoslits are gradually shunted using a copropagating optical beam. The terahertz fields are found to skirt the nanoscale photo-excited region underneath the slits, scattering to the far field and rigorously mapping the near field.