Remote Excitation of Tip-Enhanced Photoluminescence with a Parallel AgNW Coupler.
Wannes PeetersShuichi ToyouchiYasuhiko FujitaMathias WolfBeatrice FortuniEduard FronTomoko InoseJohan HofkensTakahiko EndoYasumitsu MiyataHiroshi Uji-IPublished in: ACS omega (2023)
Tip-enhanced photoluminescence (TEPL) microscopy allows for the correlation of scanning probe microscopic images and photoluminescent spectra at the nanoscale level in a similar way to tip-enhanced Raman scattering (TERS) microscopy. However, due to the higher cross-section of fluorescence compared to Raman scattering, the diffraction-limited background signal generated by far-field excitation is a limiting factor in the achievable spatial resolution of TEPL. Here, we demonstrate a way to overcome this drawback by using remote excitation TEPL (RE-TEPL). With this approach, the excitation and detection positions are spatially separated, minimizing the far-field contribution. Two probe designs are evaluated, both experimentally and via simulations. The first system consists of gold nanoparticles (AuNPs) through photoinduced deposition on a silver nanowire (AgNW), and the second system consists of two offset parallel AgNWs. This latter coupler system shows a higher coupling efficiency and is used to successfully demonstrate RE-TEPL spectral mapping on a MoSe 2 /WSe 2 lateral heterostructure to reveal spatial heterogeneity at the heterojunction.
Keyphrases
- energy transfer
- quantum dots
- gold nanoparticles
- high resolution
- single molecule
- optical coherence tomography
- label free
- living cells
- room temperature
- high speed
- sensitive detection
- atomic force microscopy
- single cell
- high throughput
- deep learning
- magnetic resonance imaging
- electron microscopy
- gene expression
- genome wide
- minimally invasive
- mass spectrometry
- computed tomography
- molecular dynamics
- real time pcr
- ionic liquid
- loop mediated isothermal amplification
- dna methylation
- electron transfer
- finite element analysis