Radially Polarized Light for Detection and Nanolocalization of Dielectric Particles on a Planar Substrate

Abstract

A fast noninvasive method based on scattering from a focused radially polarized light to detect and localize subwavelength nanoparticles on a substrate is presented. The technique relies on polarization matching in the far field between scattered and spurious reflected fields. Results show a localization uncertainty of ≈ 10 −4 λ 2 is possible for a particle of area ≈λ 2 =16. The effect of simple pupil shaping is also shown.

In Situ Characterization of Biomaterials at Solid‐Liquid Interfaces Using Ellipsometry in the UV‐Visible‐NIR Wavelength Range

“…While macro imaging ellipsometry can map surfaces of square meters, microscopic imaging ellipsometry works down to the above‐mentioned diffraction limit (not much better than one micron). Besides the cross‐sectional approach, better lateral resolution can only be achieved using tapping mode methods, such as atomic force microscopy or scanning tunneling microscopy (with special features as nano‐lithography) and numerous emerging optical methods including the near‐field approach, evanescent‐wave enhancement, scatterometry, or nanospheres . However, these methods do not provide information on the bulk layer optical properties.…”

Accurate Feeding of Nanoantenna by Singular Optics for Nanoscale Translational and Rotational Displacement Sensing

“…The singularity usually refers to the discontinuity or undefined value in the light field itself. Around these singularities of the fields, rapidly spatially varying field patterns occur, which has led to new applications such as high-precision nanoscale metrology and superresolution imaging [13,[15][16][17][18][19][20][21][22][23].In this Letter, we use two different kinds of singularities: The so-called V-point polarization singularity in an azimuthally polarized beam [24][25][26] and the phase singularity in a Hermite-Gaussian beam to precisely excite one individual element of two identical parallel metallic nanorod antennas separated by a deep subwavelength gap. The precise alignment of the singularity with the two nanorods gives an accurate feeding of them far beyond the diffraction limit.…”

“…The singularity usually refers to the discontinuity or undefined value in the light field itself. Around these singularities of the fields, rapidly spatially varying field patterns occur, which has led to new applications such as high-precision nanoscale metrology and superresolution imaging [13,[15][16][17][18][19][20][21][22][23].…”

Exploiting evanescent-wave amplification for subwavelength low-contrast particle detection

“…The resulting scattered field is recorded by a detector placed in the far field. Generally speaking, once illuminated by a focused field, the scattered field in a specific direction consists of mainly three components [28], as shown in Fig. 1(a).…”