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

Excitons, Coulomb-bound electron and hole pairs, are elementaryphoto-excitations in semiconductors, that can couple directly to light throughradiative relaxation. In contrast to these bright excitons, dark excitonsX$\rm{_D}$ with anti-parallel electron spin polarization exist, with generallyforbidden radiative emission. Because of their associated long lifetimes, thesedark excitons are appealing candidates for quantum computing andopto-electronic devices. However, optical read-out and control of X$\rm{_D}$states have remained a major challenge due to their decoupling from light.Here, we present a novel tip-enhanced nano-optical approach to precisely switchand programmably modulate the X$\rm{_D}$ emission even at room temperature.Using monolayer two-dimensional transition metal dichalcogenide (TMD)WSe$\rm{_2}$ on a gold film as model system, we demonstrate ${\sim} 6 \times10^5$-fold enhancement in dark exciton photoluminescence quantum yield. This isachieved by the unique coupling of the nano-optical antenna-tip to the darkexciton \textit{out-of-plane} optical dipole moment, with an extraordinaryPurcell factor of $\ge 2 \times 10^3$ of the tip-sample nano-cavity. Comparedto the necessity of cryogenic temperatures and high magnetic fields inconventional approaches, our work provides a new way to harness excitonicproperties in low-dimensional semiconductors and new strategies for quantumopto-electronic devices.

Radiative control of dark excitons at room temperature by nano-optical antenna-tip induced Purcell effect