Sub-wavelength resolution in linear arrays of plasmonic particles

It is important to be able to image biological samples in a manner that is non-invasive and allows the sample to retain its functionality during imaging.A member of the SPM (scanning probe microscopy) family, SNOM (scanning near-field optical microscopy), has emerged as a technique that allows optical and topographic imaging of biological samples whilst satisfying the above stated criteria. The basic operating principle of SNOM is as follows. Light is coupled down a fibre-optic probe with an output aperture of sub-wavelength dimensions. The probe is then scanned over the sample surface from a distance that is approximately equal to the size of its aperture. By this apparently simple arrangement, the diffraction limit posed by conventional optical microscopy is overcome and simultaneous generation of optical and topographic images of sub-wavelength resolution is made possible. Spatial resolution values of lOOnm in air and 60nm in liquid[1,2] are achievable with SNOM.

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Fourier optics approach to imaging with sub-wavelength resolution through metal-dielectric multilayers

Opto-Electronics Review ◽

10.2478/s11772-010-0044-5 ◽

2010 ◽

Vol 18 (4) ◽

Cited By ~ 7

Author(s):

R. Kotyński

Keyword(s):

Point Spread Function ◽

Imaging System ◽

Diffraction Theory ◽

Spatial Filter ◽

Fourier Optics ◽

Point Spread ◽

Spread Function ◽

Point Spread Function Engineering ◽

Wavelength Resolution ◽

Sub Wavelength

AbstractMetal-dielectric layered stacks for imaging with sub-wavelength resolution are regarded as linear isoplanatic systems — a concept popular in Fourier optics and in scalar diffraction theory. In this context, a layered flat lens is a one-dimensional spatial filter characterised by the point spread function. However, depending on the model of the source, the definition of the point spread function for multilayers with sub-wavelength resolution may be formulated in several ways. Here, a distinction is made between a soft source and hard electric or magnetic sources. Each of these definitions leads to a different meaning of perfect imaging. It is shown that some simple interpretations of the PSF, such as the relation of its width to the resolution of the imaging system are ambiguous for the multilayers with sub-wavelenth resolution. These differences must be observed in point spread function engineering of layered systems with sub-wavelength sized PSF.

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Optimized low-loss multilayers for imaging with sub-wavelength resolution in the visible wavelength range

Journal of Applied Physics ◽

10.1063/1.3573479 ◽

2011 ◽

Vol 109 (8) ◽

pp. 084302 ◽

Cited By ~ 19

Author(s):

Anna Pastuszczak ◽

Rafał Kotyński

Keyword(s):

Wavelength Range ◽

Low Loss ◽

Visible Wavelength ◽

Visible Wavelength Range ◽

Wavelength Resolution ◽

Sub Wavelength

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Study of Hot Spots Probing Based on Meta-Pillars Array

Journal of Computational and Theoretical Nanoscience ◽

10.1166/jctn.2019.8483 ◽

2019 ◽

Vol 16 (9) ◽

pp. 3692-3697

Author(s):

Yisha You ◽

Fujuan Huang ◽

Yongqi Fu ◽

Shaoli Zhu

Keyword(s):

Hot Spots ◽

Near Field ◽

Optical Microscope ◽

Microscopic Imaging ◽

Secondary Sources ◽

Imaging Application ◽

Calculation Results ◽

Wavelength Resolution ◽

Near Field Scanning ◽

Sub Wavelength

Inspired by imaging principle of near-field scanning optical microscope (NSOM), meta-pillars array is designed and analyzed on the basis of microscopic imaging application with high resolution. Finely focused spots acting as tiny secondary sources for illumination at near-field can be derived under supporting of the meta-pillars for the purpose of increasing imaging resolution. Numerical calculation is carried out on the basis of finite difference and time domain (FDTD) algorithm. Our calculation results demonstrate that the meta-pillars are capable of supporting the microscopic imaging at sub-wavelength resolution.

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