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Z. Wang and B. Luk’yanchuk
Fig. 15.5 a Schematic of the simulation setup consisting of the substrate target, microsphere, and
lens pair. b Light intensity (|E| 2 ) distribution induced by a transverse dipole (x–y dipole), and c a
longitudinal dipole (z-dipole), in air with a microsphere lens of diameter 6 μm and refractive index
n = 1.4. The dashed lines indicate the imaging plane (reproduced from [45], with permission from
AIP Publishing). d Table of magnification and resolution for different substrates. SUB: Substrate,
MAG: magnification, RES: resolution. e Numerically simulated point dipole parallel-to-surface
evanescent wavevector decoupling process, from near-field to far-field
imaging resolution for air (without substrate), aluminium oxide (Al 2 O 3 ) and fused
silica (SiO 2 ) are 0.28λ, 0.24λ and 0.26λ, and magnification 6, 6.6 and 6.4, respectively. Another numerical simulation performed by us, as shown in Fig. 15.5e, reveals
complex nature of high spatial frequency evanescent wave decoupling process from
sample surface [33]. A parallel-to-surface wave vector, marked by the red solid line,
was scattered by the particle, converting into propagating beam transferring to the
far-field (red dashed line). Very recently, Brettin and Astratov et al. demonstrated the
resolution can be enhanced by coupling of fluorescent objects to plasmonic metasurfaces (engineered substrate) [94].
Z. Wang and B. Luk’yanchuk
Fig. 15.5 a Schematic of the simulation setup consisting of the substrate target, microsphere, and
lens pair. b Light intensity (|E| 2 ) distribution induced by a transverse dipole (x–y dipole), and c a
longitudinal dipole (z-dipole), in air with a microsphere lens of diameter 6 μm and refractive index
n = 1.4. The dashed lines indicate the imaging plane (reproduced from [45], with permission from
AIP Publishing). d Table of magnification and resolution for different substrates. SUB: Substrate,
MAG: magnification, RES: resolution. e Numerically simulated point dipole parallel-to-surface
evanescent wavevector decoupling process, from near-field to far-field
imaging resolution for air (without substrate), aluminium oxide (Al 2 O 3 ) and fused
silica (SiO 2 ) are 0.28λ, 0.24λ and 0.26λ, and magnification 6, 6.6 and 6.4, respectively. Another numerical simulation performed by us, as shown in Fig. 15.5e, reveals
complex nature of high spatial frequency evanescent wave decoupling process from
sample surface [33]. A parallel-to-surface wave vector, marked by the red solid line,
was scattered by the particle, converting into propagating beam transferring to the
far-field (red dashed line). Very recently, Brettin and Astratov et al. demonstrated the
resolution can be enhanced by coupling of fluorescent objects to plasmonic metasurfaces (engineered substrate) [94].