The complex dispersion relation of surface plasmon polaritons at gold/para-hexaphenylene interfaces

Micro-spectroscopy of Buried Short-Range Surface Plasmon Polaritons Supported by Thin Polycrystalline Gold Films

“…The sputtering process exhibits no constraints on crystal growth, leading to the formation of a polycrystalline film with arbitrary grain orientation. Due to an excellent agreement of our current and past experimental findings (e.g., [30]) if permittivity data for evaporated gold from [31] is used, we expect a morphology similar to the one discussed by Olmon and coworkers in that publication. In the second experimental scheme, the sample was excited from the front side under In both images, the gaps in the gold films indicate the 4-µm-wide slits fabricated through FIB and providing coupling edges for SPP excitation using NIR laser pulses a fixed angle of incidence of 65° toward the sample surface normal by the same transform-limited laser pulses (see Fig.…”

“…This treatment is required to lower the work function in order to facilitate a two-photon photoemission (2PPE) process with the near-infrared laser pulses. SPP propagation (real and imaginary part of the SPP wave vector) is not affected in the applied coverage regime within the resolution of our experiment [30]. PEEM image analysis was done using the software Fiji [32].…”

Femtosecond time-resolved photoemission electron microscopy operated at sample illumination from the rear side

“…In past studies, we have shown that the deposition of small amounts of cesium onto a gold sample does not affect the propagation properties of SPPs within the resolution of the PEEM instrument. 25…”

Imaging and controlling plasmonic interference fields at buried interfaces

“…Recent advances in TR-PEEM methods have facilitated the successful spatiotemporal mapping of localized and propagating surface plasmons in a variety of systems 14 15 16 17 18 , even allowing for experimental access to plasmon phases 19 20 . Furthermore, both NSOM and TR-PEEM have demonstrated sensitivity towards probing the near-field corresponding to SPPs confined to sub-surface interfaces with a spatial resolution of up to 40 nm (refs 19 , 21 , 22 , 23 ). However, as TR-PEEM relies on sample-emitted photoelectrons, and scanning-tip-based techniques require physical probe proximity to the evanescent field, both are inherently limited to the study of electromagnetic near-fields that are external to materials.…”