Ultrafast Imaging of Surface Plasmons Propagating on a Gold Surface

Journal Article · Wed May 13 00:00:00 EDT 2015 · Nano Letters, 15(5):3472-3478

DOI:https://doi.org/10.1021/acs.nanolett.5b00803· OSTI ID:1208727

Gong, Yu; Joly, Alan G.; Hu, Dehong; El-Khoury, Patrick Z.; Hess, Wayne P.

We record time-resolved nonlinear photoemission electron microscopy (tr-PEEM) images of propagating surface plasmons (PSPs) launched from a lithographically patterned rectangular trench on a flat gold surface. Our tr-PEEM scheme involves a pair of identical, spatially separated, and interferometrically-locked femtosecond laser pulses. Power dependent PEEM images provide experimental evidence for a sequential coherent nonlinear photoemission process, in which one laser source creates a PSP polarization state through a linear interaction, and the second subsequently probes the prepared state via two photon photoemission. The recorded time-resolved movies of a PSP allow us to directly measure various properties of the surface-bound wave packet, including its carrier wavelength (785 nm) and group velocity (0.95c). In addition, tr-PEEM in concert with finite-difference time domain simulations together allow us to set a lower limit of 75 μm for the decay length of the PSP on a 100 nm thick gold film.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1208727
• Report Number(s): PNNL-SA-108438; 48129; KC0301020
• Journal Information: Nano Letters, 15(5):3472-3478, Journal Name: Nano Letters, 15(5):3472-3478
• Country of Publication: United States
• Language: English

Related Subjects

Environmental Molecular Sciences Laboratory