Nanoscale high-intensity light focusing with pure dielectric nonspherical scatterer

Sundaram, Vijay M.; Wen, Sy-Bor

doi:10.1364/ol.39.000582

Cited by 12 publications

(2 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, the photonic nanojet shaping by a simple and cheap way is an interesting research topic for the far-field projection system. The non-spherical micromedia of various spatial shapes, such as microellipses, microcones, micropyramids and microcuboids, have been intensely studied in recent years [21][22][23][24][25][26][27][28][29][30][31][32]. Such non-spherical micro-media are very attractive because they have unique ability to modify the spatial distribution of the lightwave in specific formations.…”

Section: Introductionmentioning

confidence: 99%

Geometric effect on photonic nanojet generated by dielectric microcylinders with non-cylindrical cross-sections

Liu

Lin

2016

Optics Communications

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Geometric effect on photonic nanojet generated by dielectric microcylinders with non-cylindrical cross-sections

Liu

Lin

2016

Optics Communications

View full text Add to dashboard Cite

“…Singular scattering from a wedge or a cone has been known for decades. 17,18 It is only recently that numerical simulation 19 has revealed that field focusing by this singular scattering can effect a five-order intensity enhancement that is frequency independent. This intense tip scattering produces a local light source at the tip that does not suffer from conduction loss.…”

mentioning

confidence: 99%

Diffraction-limited ultrasensitive molecular nano-arrays with singular nano-cone scattering

2014

View full text Add to dashboard Cite

Large-library fluorescent molecular arrays remain limited in sensitivity (1 Â 10 6 molecules) and dynamic range due to background auto-fluorescence and scattering noise within a large (20-100 lm) fluorescent spot. We report an easily fabricated silica nano-cone array platform, with a detection limit of 100 molecules and a dynamic range that spans 6 decades, due to point (10 nm to 1 lm) illumination of preferentially absorbed tagged targets by singular scattering off wedged cones. Its fluorescent spot reaches diffraction-limited submicron dimensions, which are 10 4 times smaller in area than conventional microarrays, with comparable reduction in detection limit and amplification of dynamic range. Commercially available fluorescent micro-arrays based on target labeling, northern blot, or enzyme-linked immunosorbent assay (ELISA) are limited to a detection threshold of 1 to 10 Â 10 6 molecules per fluorescent spot, 1-23 thus requiring cell culturing or Polymerase Chain Reaction (PCR) amplification for many applications. The low sensitivity is often due to broad illumination, which creates auto-fluorescence noise. Even if point illumination and pin-hole filtering of non-focal plane noise are implemented in a confocal setup, the large and non-uniform fluorescent spots create scattering noise over each 20-100 lm element, which degrades the detection limit. 4 Smaller spots can, in theory, be introduced by nano-sprays and nano-imprinting. However, directing the targets to such small areas then becomes problematic. Real-time PCR is, in principle, capable of detecting a single molecule but is limited in its target number 5 and is hence slow/ expensive for large-library assays. A large-library platform with much better detection limit than the current fluorescent microarrays would transform many screening assays. Ideally, this platform would not use the confocal configuration. Instead, it would direct the target molecules to a submicron spot and illuminate them with a nearby point source that does not require scanning.A promising platform is the optical fiber bundle array, 6 with more than 10 4 fibers and targets, in principle. With its endoscopic configuration, these fiber bundles are most convenient for in situ and real-time biosensing modalities in microfluidic biochips and microfluidic 3-D cell cultures. Consequently, the optical sensing is typically carried out in the transmission mode, with the optical signals transmitted through the optical fibers to a detector. Microwell arrays at the distal end of imaging fiber, with molecular targets captured and transported to the microwells by microbeads, are the most popular among these optical fiber arrays. Although detection limit better than 1 Â 10 6 molecules per bead has been reported, the bar-coded beads limit the target number of this platform. 7,8 Our previous work 9,10 has shown that plasmonics at nanotips can enhance local electric field by three orders of magnitude. However, conduction loss and quenching of fluorescence 11,12 by the metal substrates limit the use o...

show abstract

Photonic nanojet super-resolution in immersed ordered assembly of dielectric microspheres

Geints

Zemlyanov

2017

Journal of Quantitative Spectroscopy and Radiative Transfer

View full text Add to dashboard Cite

Nanoscale high-intensity light focusing with pure dielectric nonspherical scatterer

Cited by 12 publications

References 18 publications

Geometric effect on photonic nanojet generated by dielectric microcylinders with non-cylindrical cross-sections

Geometric effect on photonic nanojet generated by dielectric microcylinders with non-cylindrical cross-sections

Diffraction-limited ultrasensitive molecular nano-arrays with singular nano-cone scattering

Photonic nanojet super-resolution in immersed ordered assembly of dielectric microspheres

Contact Info

Product

Resources

About