English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Plasmons in ultranarrow metal gaps are highly sensitive to the electrondensity profile at the metal surfaces. Using a fully quantum mechanicalapproach, we study the effects of electron spill-out on gap plasmons andreflectance from ultrasharp metal grooves. We demonstrate that the mode indexof ultranarrow gap plasmons converges to the bulk refractive index in the limitof vanishing gap and, thereby, rectify the unphysical divergence found inclassical models. Surprisingly, spill-out also significantly increases theplasmonic absorption for few-nanometer gaps and lowers the reflectance fromarrays of ultrasharp metal grooves. These findings are explained in terms ofenhanced gap plasmon absorption taking place inside the gap 1-2 {\AA} from thewalls and delocalization near the groove bottom. Reflectance calculationstaking spill-out into account are shown to be in much better agreement withmeasurements compared with classical models.

Quantum spill out in few-nanometer metal gaps: Effect on gap plasmons and reflectance from ultrasharp groove arrays