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Chen Junyan, Zhang Fei, Zhang Ming, et al. Radially polarized Bessel lens based on all-dielectric metasurface[J]. Opto-Electronic Engineering, 2018, 45(11): 180124. doi: 10.12086/oee.2018.180124
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Radially polarized Bessel lens based on all-dielectric metasurface
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Abstract
In this paper, a radially polarized Bessel lens based on a dielectric metasurface is proposed. It can efficiently convert linearly polarized light into radially polarized light and simultaneously achieve non-diffracting Bessel beams. Under the incidence of linearly polarized light, the left and right handed components of linearly polarized light are independently regulated by the asymmetric photon spin-orbit interaction. Finally, polarization conversion and wavefront control are simultaneously achieved by spin recombination. At wavelength of 532 nm, the numerical aperture NA=0.9, and the metalenses achieve a focus focal spot beyond the diffraction limit. The study has potential applications in particle acceleration and super-resolution imaging. -
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References
[1] Zhan Q W.Cylindrical vector beams:from mathematical concepts to applications[J].Advances in Optics and Photonics, 2009, 1(1):1-57. doi: 10.1364/AOP.1.000001 [2] Luo J, Zhao Z Y, Pu M B, et al.Tight focusing of radially and azimuthally polarized light with plasmonic metalens[J].Optics Communications, 2015, 356:445-450. doi: 10.1016/j.optcom.2015.08.025 [3] Zhao Y, Belkin M A, Alù A.Twisted optical metamaterials for planarized ultrathin broadband circular polarizers[J].Nature Communications, 2012, 3:870. doi: 10.1038/ncomms1877 [4] Luo J, Yu H L, Song M W, et al.Highly efficient wavefront manipulation in terahertz based on plasmonic gradient metasurfaces[J].Optics Letters, 2014, 39(8):2229-2231. doi: 10.1364/OL.39.002229 [5] Gao H, Pu M B, Li X, et al.Super-resolution imaging with a Bessel lens realized by a geometric metasurface[J].Optics Express, 2017, 25(12):13933-13943. doi: 10.1364/OE.25.013933 [6] Guo Y, Wang Y, Pu M, et al.Dispersion management of anisotropic metamirror for super-octave bandwidth polarization conversion[J].Scientific Reports, 2015, 5(1): 8434. doi: 10.1038/srep08434 [7] Aieta F, Genevet P, Kats M A, et al. Aberration-free ultrathin flat lenses and axicons at telecom wavelengths based on plasmonic metasurfaces[J].Nano Letters, 2012, 12(9): 4932-4936. doi: 10.1021/nl302516v [8] Gao X M, Wang J, Gu H T, et al.Focusing properties of concentric piecewise cylindrical vector beam[J].Optik-International Journal for Light and Electron Optics, 2007, 118(6):257-265. doi: 10.1016/j.ijleo.2006.10.006 [9] Man Z S, Fu S G, Wei G X.Focus engineering based on analytical formulae for tightly focused polarized beams with arbitrary geometric configurations of linear polarization[J].Journal of the Optical Society of America A, 2017, 34(8):1384-1391. doi: 10.1364/JOSAA.34.001384 [10] Stafeev S S, Kotlyar V V, Nalimov A G, et al. Subwavelength gratings for polarization conversion and focusing of laser light[J]. Photonics and Nanostructures-Fundamentals and Applications, 2017, 27:32-41. [11] Yu N, Capasso F.Flat optics with designer metasurfaces[J].Nature Materials, 2014, 13(2): 139-150. doi: 10.1038/nmat3839 [12] Zhang F, Yu H L, Fang J W, et al. Efficient generation and tight focusing of radially polarized beam from linearly polarized beam with all-dielectric metasurface[J].Optics Express, 2016, 24(6):6656-6664. doi: 10.1364/OE.24.006656 [13] Zhang B Z.Polarization vortex spatial optical solitons in Bessel optical lattices[J].Physics Letters A, 2011, 375(7): 1110-1115. doi: 10.1016/j.physleta.2011.01.027 [14] El Halba E M, Boustimi M, Ez-zariy L, et al. Focusing properties of radially polarized Bessel-like beam with radial cosine phase wavefront by a high numerical aperture objective[J].Optical and Quantum Electronics, 2017, 49(6):220. doi: 10.1007/s11082-017-1050-3 [15] Chen H, Ling X H, Li Q G, et al. Generation of double-ring-shaped cylindrical vector beams by modulating Pancharatnam-Berry phase[J].Optik-International Journal for Light and Electron Optics, 2017, 134:227-232. doi: 10.1016/j.ijleo.2017.01.052 [16] Li X, Pu M B, Zhao Z Y, et al.Catenary nanostructures as compact Bessel beam generators[J].Scientific Reports, 2016, 6:20524. doi: 10.1038/srep20524 [17] Pfeiffer C, Grbic A.Controlling vector Bessel beams with metasurfaces[J].Physical Review Applied, 2014, 2(4): 044012. doi: 10.1103/PhysRevApplied.2.044012 [18] Yew E Y S, Sheppard C J R.Tight focusing of radially polarized Gaussian and Bessel-Gauss beams[J].Optics Letters, 2007, 32(23):3417-3419. doi: 10.1364/OL.32.003417 [19] Wu G F, Wang F, Cai Y J.Generation and self-healing of a radially polarized Bessel-Gauss beam[J].Physical Review A, 2014, 89(4):043807. doi: 10.1103/PhysRevA.89.043807 [20] Guo Y H, Pu M B, Zhao Z Y, et al.Merging geometric phase and plasmon retardation phase in continuously shaped metasurfaces for arbitrary orbital angular momentum generation[J].ACS Photonics, 2016, 3(11):2022-2029. doi: 10.1021/acsphotonics.6b00564 [21] Zhang F, Pu M B, Luo J, et al.Symmetry breaking of photonic spin-orbit interactions in metasurfaces[J].Opto-Electronic Engineering, 2017, 44(3):319-325, 371. doi: 10.3969/j.issn.1003-501X.2017.03.006 [22] Khonina S N, Karpeev S V, Paranin V D, et al. Polarization conversion under focusing of vortex laser beams along the axis of anisotropic crystals[J].Physics Letters A, 2017, 381(30): 2444-2455. doi: 10.1016/j.physleta.2017.05.025 [23] Yu J J, Zhou C H, Jia W, et al. Generation of tightly focused twin Bessel beams using circular Dammann gratings under radial polarization incidence[J].Optics Communications, 2012, 285(21-22): 4166-4170. doi: 10.1016/j.optcom.2012.06.079 [24] Zheng C L, Petersen T C, Kirmse H, et al. Axicon lens for electrons using a magnetic vortex:the efficient generation of a Bessel beam[J].Physical Review Letters, 2017, 119(17):174801. doi: 10.1103/PhysRevLett.119.174801 [25] Liu Y C, Ke Y G, Zhou J X, et al. Generation of perfect vortex and vector beams based on Pancharatnam-Berry phase elements[J].Scientific Reports, 2017, 7:44096. doi: 10.1038/srep44096 [26] Dorn R, Quabis S, Leuchs G.The focus of light—linear polarization breaks the rotational symmetry of the focal spot[J].Journal of Modern Optics, 2003, 50(12):1917-1926. doi: 10.1080/09500340308235246 -
Overview
Overview:In the past few decades, cylindrical vector waves have received more and more attention due to their uniqueproperties in focusing and imaging, especially radial polarized light (RPL). RPL is an axisymmetrically polarized beamwith a strong longitudinal component in the focal plane, which allows RPL focusing to produce a tighter focal spot.Nowadays, it has been reported that RPL can be used to realize metalenses. However, most of the common metalensesbased on RPL use spherical phase gradient to design the lens, which results in the influence of diffraction. The full widthat half maximum (FWHM) of the focused spot cannot exceed the diffraction limit. Bessel non-diffracting beam is abeam with the advantages of small center spot, high concentration of light intensity, good directivity, and maximumnon-diffraction distance. Although many studies have been conducted on non-diffracted beams today, no existed metalen can combine the advantages of these two types of beams. In order to design a metalens that exceeds the diffractionlimit, a RPL Bessel lens based on a dielectric metasurface is proposed in this paper. It can efficiently convert linearlypolarized light into radially polarized light and simultaneously achieve non-diffracting Bessel beams. In order to achievesuch design, we need to control the polarization and phase of the incident beam at the same time. In this paper, asymmetric photon spin-orbit interaction is used to achieve arbitrary control of wavefront phase and polarization state simultaneously. Photon SOI describes the coupling relationship between photon spin angular momentum (SAM) andorbital angular momentum (OAM) during light transmission. By separately controlling the size and rotation of the unitcell, the phase and the geometric phase of the waveguide can be introduced at the same time. The combination of thetwo phase gradients can realize the asymmetric photon SOI and further realize independent control of the LCPL and theRCPL. This feature can be used to achieve arbitrary independence. Under linearly polarized light, the left and righthanded components of linearly polarized light are independently regulated by the asymmetric photon SOI. Polarizationconversion and wavefront control are simultaneously achieved by spin recombination. In this paper, the RPL Besselfocusing and RPL spherical focusing simulation results are compared with each other, the FWHM of the two lenses isapproximately 360 nm and 315 nm, respectively. Comparing the simulation results, the RPL Bessel focus has a smallerfocal spot and exceeds the diffraction limit (the diffraction limit is r=0.61λ/NA=360 nm).
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Chen Junyan, Zhang Fei, Zhang Ming, et al. Radially polarized Bessel lens based on all-dielectric metasurface[J]. Opto-Electronic Engineering, 2018, 45(11): 180124. doi: 10.12086/oee.2018.180124
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Figure 1.
Unit cell design. (a) Schematic diagram of a radially polarized Bessel metalens; (b) Schematic diagram of the unit cell; (c)~(e) Side view and top view of the unit cell; (f) The simulated spin-independent phases and cross-polarized and co-polarized transmissivities of eight unit cells at the wavelength of 532 nm. The materials of nanofins and substrate are titanium dioxide (TiO2) and silicon dioxide (SiO2). Constant parameters: H=600 nm, P=370 nm, R=30 nm. The nanofins sizes (L and W) of unit cells from 1 to 4 are L=300 nm, 290 nm, 250 nm, 235 nm, W=120 nm, 105 nm, 95 nm, 80 nm. The unit cells from 5 to 8 are acquired by rotating the posts from 1 to 4 by an angle of 90° clockwise in (f). Simulations use the finite element method (FEM) in CST microwave studio. The refractive indices are given as 2.43 (TiO2), 1.46 (SiO2), respectively
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Figure 2.
Schematic of designing the spherical focusing lens and Bessel lens. (a) To focus a plane wave into a focal spot at a distance f from the plane, a hyperboloid phase distribution must be applied to the incident wavefront. The phase shift at the point PL is propor tional to the distance PLSL, where SL is the projection of PL on a spherical surface equal to the radius of the focal length f; (b) The point light source is imaged on a line segment along the optical axis. The length of the segment is the depth of focus (DOF). The phase of the point PA on the PA plane is proportional to the distance of the PASA, where SA is the projection of the PA on the cone, and the vertex is located at the intersection of the zoom surface and the optical axis. The angle β=arctan(r/DOF) (r is the radius of the facet). (c) The hyperbolic radial phase distribution generated on the spherical focusing lens; (d) The conical radial phase distribution produced on the flat axicon
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Figure 3.
Focus results for A and B lenses. (a) Focused results of the theoretical calculation of the A lens; (b) Focused results of B-lens theoretical calculations; (c) Simulation focus results of the A lens; (d) Simulation focus results of the B lens; (e) The transverse line in 3(a) and 3(b) at y = 0 μm; (f) The transverse line in 3(c) and 3(d) at y=0 μm
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Figure 4.
The electric field intensity distributions of the focal plane of B lens. (a) The total field; (b) The normalized intensity of FIT simulation; (c) The sum of radial component; (d) The sum of longitudinal component
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Figure 5.
xoz longitudinal cross-section results for the A and B lens focal points. (a), (b) Theoretical calculations and simulation results for the intensity distribution of the x-z plane of the A-lens; (c) Theoretical results and simulation results of the normalized intensity distribution curve of the A-lens optical axis; (d), (e) Theoretical calculations and simulation results for the intensity distribution of B-lens x-z plane; (f) Theoretical results and simulation results of the normalized intensity distribution curve of the B-lens optical axis
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Figure 6.
(a), (b) Intensity distribution of focal plane (z=4.74 μm) and xoz plane of C-lens when x-polarized light is incident; (c) B lens focal plane (z=4.76 μm) intensity distribution; (d) The horizontal axis at y=0 in 6(a) and 6(c)
