基于二维光子晶体负折射的共聚焦系统
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摘要
基于二维光子晶体的负折射和亚波长成像特性,提出了一种可以实现超分辨成像的共聚焦系统,使用时域有限差分法(FDTD)仿真了共聚焦系统的聚焦和成像的过程。在焦点离光子晶体透镜下表面1.55μm处,横坐标X=4μm时,焦点半峰全宽(FWHM)为0.593λ,小于入射波长,此时反射光在右侧像点的FWHM达到0.496λ,实现了超分辨成像,并且随着焦点的右移,像点FWHM不断减小。同时,在针孔和焦点位置不变时共聚焦系统的轴向分辨率达到2.2λ。
In this study,a confocal system is proposed for which super-resolution imaging can be achieved based on the negative refraction and subwavelength imaging characteristics of two-dimensional photonic crystals(PCs).Further,the focusing and imaging processes of a confocal system are simulated with the finite-difference timedomain method.When the distance from the focus to the lower surface of a PC becomes 1.55μm and when the transverse coordinate x=4,the full width at half maximum(FWHM)of the focus becomes 0.593λ,which is less than the incident wavelength;further,the FWHM of the reflected light in the right of the image point becomes0.496λ,which indicates that super-resolution imaging can be realized.The FWHM of the image point decreases continuously when the focus shifts to right;further,the axial resolution of the confocal system becomes 2.2λwhen the pinhole and focus are fixed.
In this study,a confocal system is proposed for which super-resolution imaging can be achieved based on the negative refraction and subwavelength imaging characteristics of two-dimensional photonic crystals(PCs).Further,the focusing and imaging processes of a confocal system are simulated with the finite-difference timedomain method.When the distance from the focus to the lower surface of a PC becomes 1.55μm and when the transverse coordinate x=4,the full width at half maximum(FWHM)of the focus becomes 0.593λ,which is less than the incident wavelength;further,the FWHM of the reflected light in the right of the image point becomes0.496λ,which indicates that super-resolution imaging can be realized.The FWHM of the image point decreases continuously when the focus shifts to right;further,the axial resolution of the confocal system becomes 2.2λwhen the pinhole and focus are fixed.
引文
[1] Veselago V G.The electrodynamics of substanceswith simultaneously negative values ofεandμ[J].Soviet Physics Uspekhi,1968,10(4):509-514.
[2] Pendry J B.Negative refraction makes a perfect lens[J].Physical Review Letters,2000,85(18):3966-3969.
[3] Kang M,Chen J,Li S M,et al.Optical spin-dependent angular shift in structured metamaterials[J].Optics Letters,2011,36(19):3942-3944.
[4] John S.Strong localization of photons in certaindisordered dielectric superlattices[J]. PhysicalReview Letters,1987,58(23):2486-2489.
[5] Yablonovitch G,Sheng P,Yablonovitch E,et al.Inhibited spontaneous emission in solid-state physicsand electronics[J].Physical Review Letters,1987,58(20):2059-2061.
[6] Su K, Wang Z M,Liu J J.Three waveguidesdirectional coupler based on two dimensional squarelattice photonic crystal[J].Acta optica Sinica,2016,36(3):0323002.苏康,王梓名,刘建军.二维正方晶格光子晶体三光波导方向耦合器[J].光学学报,2016,36(3):0323002.
[7] Zhang X X,Chen H M.Design and performanceanalysis of photonic crystal polarizing beam splitter[J].Laser &Optoelectronics Progress,2017,54(1):011301.张信祥,陈鹤鸣.光子晶体偏振分束器的设计与性能分析[J].激光与光电子学进展,2017,54(1):011301.
[8] Ma J,Yu H H,Xiong J G,et al.Research progressof photonic crystal fiber sensors[J].Laser &Optoelectronics Progress,2017,54(7):070006.马健,余海湖,熊家国,等.光子晶体光纤传感器研究进展[J].激光与光电子学进展,2017,54(7):070006.
[9] Cubukcu E, Aydin K, Ozbay E, et al.Electromagnetic waves:negative refraction byphotonic crystals[J].Nature,2003,423(6940):604-605.
[10] Parimi P V,Lu W T,Vodo P,et al.Photoniccrystals:imaging by flat lens using negativerefraction[J].Nature,2003,426(6965):404.
[11] Liu F F,Zhu Z J,Tong Y W.Effects on imagingquality of defects in the photonic crystal with negativerefraction material[J].Acta Optica Sinica,2015,35(4):0416004.刘逢芳,朱兆杰,童元伟.光子晶体负折射材料中缺陷对成像质量的影响[J].光学学报2015,35(4):0416004.
[12] Luo C,Johnson S G,Joannopoulos J D,et al.Subwavelength imaging in photonic crystals[J].Physical Review B,2003,68(4):045115.
[13] PetráňM, Hadravsky′ M,Egger M D,et al.Tandem-scanning reflected light microscope[J].Journal of the Optical Society of America,1968,58(5):661-664.
[14] Kuang C F,Li S,Liu W,et al.Breaking thediffraction barrier using fluorescence emissiondifference microscopy[J].Scientific Reports,2013,3:1441.
[15] Willig KI, Harke B, Medda R,et al.STEDmicroscopy with continuous wave beams[J].NatureMethods,2007,4(11):915-918.
[16] Zhao G,Kabir M M,Toussaint K C,et al.Saturated absorption competition microscopy[J].Optica,2017,4(6):633-636.
[17] Rong Z H,Li S,Kuang C F,et al.Real-time super-resolution imaging by high-speed fluorescenceemission difference microscopy[J].Journal ofModern Optics,2014,61(16):1364-1371.
[18] Wilson T.Resolution and optical sectioning in theconfocal microscope[J].Journal of Microscopy,2011,244(2):113-121.
[19] Sun T X,Liu H H,Liu Z G,et al.Application ofconfocal micro X-ray fluorescence technique based onpolycapillary X-ray lens in analyzing medicine withcapsule[J].Acta Optica Sinica,2014,34(1):0134001.孙天希,刘鹤贺,刘志国,等.毛细管X光透镜共聚焦微束X射线荧光技术在胶囊类药品分析中的应用[J].光学学报,2014,34(1):0134001.
[20] Borlinghaus R T,Kappel C.HyVolution:the smartpath to confocal super-resolution[J]. NatureMethods,2016,13(3):276.
[2] Pendry J B.Negative refraction makes a perfect lens[J].Physical Review Letters,2000,85(18):3966-3969.
[3] Kang M,Chen J,Li S M,et al.Optical spin-dependent angular shift in structured metamaterials[J].Optics Letters,2011,36(19):3942-3944.
[4] John S.Strong localization of photons in certaindisordered dielectric superlattices[J]. PhysicalReview Letters,1987,58(23):2486-2489.
[5] Yablonovitch G,Sheng P,Yablonovitch E,et al.Inhibited spontaneous emission in solid-state physicsand electronics[J].Physical Review Letters,1987,58(20):2059-2061.
[6] Su K, Wang Z M,Liu J J.Three waveguidesdirectional coupler based on two dimensional squarelattice photonic crystal[J].Acta optica Sinica,2016,36(3):0323002.苏康,王梓名,刘建军.二维正方晶格光子晶体三光波导方向耦合器[J].光学学报,2016,36(3):0323002.
[7] Zhang X X,Chen H M.Design and performanceanalysis of photonic crystal polarizing beam splitter[J].Laser &Optoelectronics Progress,2017,54(1):011301.张信祥,陈鹤鸣.光子晶体偏振分束器的设计与性能分析[J].激光与光电子学进展,2017,54(1):011301.
[8] Ma J,Yu H H,Xiong J G,et al.Research progressof photonic crystal fiber sensors[J].Laser &Optoelectronics Progress,2017,54(7):070006.马健,余海湖,熊家国,等.光子晶体光纤传感器研究进展[J].激光与光电子学进展,2017,54(7):070006.
[9] Cubukcu E, Aydin K, Ozbay E, et al.Electromagnetic waves:negative refraction byphotonic crystals[J].Nature,2003,423(6940):604-605.
[10] Parimi P V,Lu W T,Vodo P,et al.Photoniccrystals:imaging by flat lens using negativerefraction[J].Nature,2003,426(6965):404.
[11] Liu F F,Zhu Z J,Tong Y W.Effects on imagingquality of defects in the photonic crystal with negativerefraction material[J].Acta Optica Sinica,2015,35(4):0416004.刘逢芳,朱兆杰,童元伟.光子晶体负折射材料中缺陷对成像质量的影响[J].光学学报2015,35(4):0416004.
[12] Luo C,Johnson S G,Joannopoulos J D,et al.Subwavelength imaging in photonic crystals[J].Physical Review B,2003,68(4):045115.
[13] PetráňM, Hadravsky′ M,Egger M D,et al.Tandem-scanning reflected light microscope[J].Journal of the Optical Society of America,1968,58(5):661-664.
[14] Kuang C F,Li S,Liu W,et al.Breaking thediffraction barrier using fluorescence emissiondifference microscopy[J].Scientific Reports,2013,3:1441.
[15] Willig KI, Harke B, Medda R,et al.STEDmicroscopy with continuous wave beams[J].NatureMethods,2007,4(11):915-918.
[16] Zhao G,Kabir M M,Toussaint K C,et al.Saturated absorption competition microscopy[J].Optica,2017,4(6):633-636.
[17] Rong Z H,Li S,Kuang C F,et al.Real-time super-resolution imaging by high-speed fluorescenceemission difference microscopy[J].Journal ofModern Optics,2014,61(16):1364-1371.
[18] Wilson T.Resolution and optical sectioning in theconfocal microscope[J].Journal of Microscopy,2011,244(2):113-121.
[19] Sun T X,Liu H H,Liu Z G,et al.Application ofconfocal micro X-ray fluorescence technique based onpolycapillary X-ray lens in analyzing medicine withcapsule[J].Acta Optica Sinica,2014,34(1):0134001.孙天希,刘鹤贺,刘志国,等.毛细管X光透镜共聚焦微束X射线荧光技术在胶囊类药品分析中的应用[J].光学学报,2014,34(1):0134001.
[20] Borlinghaus R T,Kappel C.HyVolution:the smartpath to confocal super-resolution[J]. NatureMethods,2016,13(3):276.