Interplay of hot electrons from localized and propagating plasmons

Abstract

Plasmon-induced hot-electron generation has recently received considerable interest and has been studied to develop novel applications in optoelectronics, photovoltaics and green chemistry. Such hot electrons are typically generated from either localized plasmons in metal nanoparticles or propagating plasmons in patterned metal nanostructures. Here we simultaneously generate these heterogeneous plasmon-induced hot electrons and exploit their cooperative interplay in a single metal-semiconductor device to demonstrate, as an example, wavelength-controlled polarity-switchable photoconductivity. Specifically, the dual-plasmon device produces a net photocurrent whose polarity is determined by the balance in population and directionality between the hot electrons from localized and propagating plasmons. The current responsivity and polarity-switching wavelength of the device can be varied over the entire visible spectrum by tailoring the hot-electron interplay in various ways. This phenomenon may provide flexibility to manipulate the electrical output from light-matter interaction and offer opportunities for biosensors, long-distance communications, and photoconversion applications.

Photothermal Cellulose-Patch with Gold-Spiked Silica Microrods Based on Escherichia coli

“…The absorbed photon energy decays via both radiative and nonradiative damping, and then, LSPR excitations significantly increase the yield of hot electrons in the nonradiative process. 33 The lattice temperature increases through the coupling between the hot electrons and phonons of the metal lattice. Finally, the thermal energy of lattice transfers to the local environment.…”

Plasmon-Coupled Photocapacitor Neuromodulators

“…Afterward, the gold (Au) thin film is deposited and annealed to form self-assembled nanoislands. 19 , 20 The mechanism of island formation is described by Ostwald ripening of mass transport either by weakly bound individual Au atoms or small clusters combining into larger clusters. 21 The surface morphology of the plasmonic biointerface confirms the formation of gold nanoislands (AuNIs) on the photoactive layer ( Figure 1 a, right), which leads to a plasmonic peak at around 626 nm ( Figure 1 b, inset).…”

Plasmon-Coupled Photocapacitor Neuromodulators

“…1a, left), the thickness of the ZnO and PTB7-Th:PC71BM layers correspond to 52 nm and 104 nm, respectively. Afterward, gold (Au) thin film is deposited and annealed to form self-assembled nanoislands [19, 20]. The surface morphology of plasmonic biointerface confirms the formation of gold nanoislands (AuNIs) on the photoactive layer (Fig.…”