The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify th...The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify the OV mode through the analysis of interference patterns. The interference patterns of the OV source incident on the double slits can be perfectly illustrated by using both the classical double-slit interference method and the Huygens–Fresnel principle. The interference fringes will twist along the negative or positive direction of x axis when topological charge(TC)l>0 or l<0, and the degree of the movement varies with the TC, allowing for a quantitative display of the OV characteristics through the interference patterns. Additionally, we deduce analytically that the zeroth-order interference fringe has a linear relationship with the TC and the vertical position. These findings highlight the ability to identify the OV mode by analyzing the interference patterns produced by Young's doublet.展开更多
Super-resolution imaging with superlens has been one of the fundamental research topics. Unfortunately, the resolution of superlens is inevitably restrained by material loss. To address the problem, we introduce the s...Super-resolution imaging with superlens has been one of the fundamental research topics. Unfortunately, the resolution of superlens is inevitably restrained by material loss. To address the problem, we introduce the solid immersion mechanism into the slab superlens and the cylindrical superlens. The proposed solid immersion slab superlens(SISSL) and the solid immersion cylindrical superlens(SICSL) can improve the resolution by converting evanescent wave to propagating wave using high refractive index materials. From the perspective of applications, the cylindrical superlens with finite cross section and the ability of magnification or demagnification has more advantages than the slab superlens. Therefore,we focus on demonstrating analytically the super-resolution imaging of SICSL. Due to the impedance mismatching caused by solid immersion mechanism, the whispering gallery modes(WGMs) are excited between SICSL and the air interface.We clarify the excitation conditions of WGMs and analyze their influence on the imaging quality of SICSL. The SISSL and SICSL may pave a way to apply in lithography technique and real-time biomolecular imaging in future.展开更多
The energy crisis has aroused widespread concern, and the reform of energy structure is imminent. In the future,the energy structure will be dominated by the solar energy and other renewable energy sources. The solar ...The energy crisis has aroused widespread concern, and the reform of energy structure is imminent. In the future,the energy structure will be dominated by the solar energy and other renewable energy sources. The solar concentrating technology as a promising method has been widely studied for collecting solar energy. However, the previous solar concentrating technologies suffer from some drawbacks, such as low focusing efficiency and large concentrating size. The Luneburg lens with highly efficient aberration-free focusing provides a new route for solar/energy concentrator. In this work, we designed a plane focal surface Luneburg lens(PFSLL) by transformation optics(TO). The PFSLL provides a relatively high focusing efficiency and concentration ratio of collection of energy. At the same time, it circumvents the disadvantage of curve surface of the classical Luneburg lens in device integration. Based on the reciprocity of electromagnetic waves, the PFSLL can also be applied to the antenna field to achieve broadband wide-angle scanning and highly directional radiation.展开更多
We present an impedance-matched reduced version of acoustic cloaking whose mass is in a reasonable range. A layered cloak design with isotropic material is also proposed for the reduced cloak. Numerical calculations f...We present an impedance-matched reduced version of acoustic cloaking whose mass is in a reasonable range. A layered cloak design with isotropic material is also proposed for the reduced cloak. Numerical calculations from the transfer matrix methods show that the present layered cloak can reduce the scattering of an air cylinder substantially.展开更多
Super-resolution imaging is vital for optical applications, such as high capacity information transmission, real-time bio-molecular imaging, and nanolithography. In recent years, technologies and methods of super-reso...Super-resolution imaging is vital for optical applications, such as high capacity information transmission, real-time bio-molecular imaging, and nanolithography. In recent years, technologies and methods of super-resolution imaging have attracted much attention. Different kinds of novel lenses, from the superlens to the super-oscillatory lens, have been designed and fabricated to break through the diffraction limit. However, the effect of the super-resolution imaging in these lenses is not satisfactory due to intrinsic loss, aberration, large sidebands, and so on. Moreover, these lenses also cannot realize multiple super-resolution imaging. In this research, we introduce the solid immersion mechanism to Mikaelian lens(ML) for multiple super-resolution imaging. The effect is robust and valid for broadband frequencies. Based on conformal transformation optics as a bridge linking the solid immersion ML and generalized Maxwell's fish-eye lens(GMFEL), we also discovered the effect of multiple super-resolution imaging in the solid immersion GMFEL.展开更多
The propagation of acoustic waves is a fundamental topic in shallow ocean acoustics.We numerically demonstrate a three-dimensional zone of silence consisting of a circular tube with gradient index metamaterials attach...The propagation of acoustic waves is a fundamental topic in shallow ocean acoustics.We numerically demonstrate a three-dimensional zone of silence consisting of a circular tube with gradient index metamaterials attached to its rigid wall.The cloaking effect is verified by fine agreement with analytical calculations.展开更多
We propose multi-core conformal lenses by combining conformal transformation optics with absolute instruments.Depending on the cores and incident angles,the conformal lenses have tunable functionalities like focusing,...We propose multi-core conformal lenses by combining conformal transformation optics with absolute instruments.Depending on the cores and incident angles,the conformal lenses have tunable functionalities like focusing,reflection,and transparency,thereby providing a feasible general method for designing multi-functional devices.展开更多
Vortex waves with orbital angular momentum(OAM)are a highly active research topic in various fields.In this paper,we design and investigate cylindrical metagratings(CMs)with an even number of unit cells that can effic...Vortex waves with orbital angular momentum(OAM)are a highly active research topic in various fields.In this paper,we design and investigate cylindrical metagratings(CMs)with an even number of unit cells that can efficiently achieve vortex localization and specific OAM selective conversion.The multifunctional manipulation of vortex waves and the new OAM conservation law have further been confirmed through analytical calculations and numerical simulations.In addition,we qualitatively and quantitatively determine the OAM range for vortex localization and the OAM value of vortex selective conversion and also explore the stability for performance and potential applications of the designed structure.This work holds potential applications in particle manipulation and optical communication.展开更多
In this Letter,we find that Morse potential(proposed about 90 years ago)could be connected to Coulomb potential(or Newton potential)and harmonic potential(or Hooke potential)by conformal mappings.We thereby design a n...In this Letter,we find that Morse potential(proposed about 90 years ago)could be connected to Coulomb potential(or Newton potential)and harmonic potential(or Hooke potential)by conformal mappings.We thereby design a new conformal lens from Morse potential,Eaton lens,and Luneburg lens and propose a series of generalized Eaton/Luneburg lenses.We find that this Morse lens is a perfect self-focusing asymmetric lens that differs from a Mikaelian lens.Our theory provides a new insight to Morse potential and other traditional potentials,and revisits their classical applications on designing lenses.展开更多
Effective medium theory is a powerful tool to solve various problems for achieving multifarious functionalities and applications. In this article, we present a concise empirical formula about effective permittivity of...Effective medium theory is a powerful tool to solve various problems for achieving multifarious functionalities and applications. In this article, we present a concise empirical formula about effective permittivity of checkboard structures for different directions. To verify our empirical formula, we perform simulations of checkboard periodic structures in squares, rectangles, and sectors in two dimensions. Our results show that the formula is valid in a large range of parameters. This work provides a new way to understand and design composite materials, which might lead to further optical applications in transformation optics.展开更多
An illusion counter-part displays the same scattering far-field pattern as that of a real object. In this paper, for the first time, we demonstrate that such an unreal illusion can be cloaked by an external cloak. Thi...An illusion counter-part displays the same scattering far-field pattern as that of a real object. In this paper, for the first time, we demonstrate that such an unreal illusion can be cloaked by an external cloak. This phenomenon shall be called ＂cloak an illusion＂. Numerical simulations were performed to demonstrate such a phenomenon.展开更多
It is well known that cats have fascinating eyes with various colors,such as green,blue,and brown.In addition,they possess strong night vision ability,which can distinguish things clearly even in a poor light environm...It is well known that cats have fascinating eyes with various colors,such as green,blue,and brown.In addition,they possess strong night vision ability,which can distinguish things clearly even in a poor light environment.These drive us to reveal the secrets behind them.In fact,cats’ eyes can be considered as special lenses(which we would like to mimic by using a Luneburg lens).We make an analysis of the role of photonic crystals behind the lens and demonstrate that the integration of photonic crystals into Luneburg lens can be regarded as a retroreflector and greatly improve the light focusing intensity of the lens in a broad band of frequencies.This wonderful bioinspired phenomenon is expected to design more interesting and serviceable devices by combining photonic crystals with transformation optics.展开更多
基金Project supported by the National Key Research and Development Program of China (Grant Nos.2020YFA0710100 and 2023YFA1407100)the National Natural Science Foundation of China (Grant Nos.92050102 and 12374410)+2 种基金the Jiangxi Provincial Natural Science Foundation (Grant No.20224ACB201005)the Fundamental Research Funds for the Central Universities (Grant Nos.20720230102 and 20720220033)China Scholarship Council (Grant No.202206310009)。
文摘The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify the OV mode through the analysis of interference patterns. The interference patterns of the OV source incident on the double slits can be perfectly illustrated by using both the classical double-slit interference method and the Huygens–Fresnel principle. The interference fringes will twist along the negative or positive direction of x axis when topological charge(TC)l>0 or l<0, and the degree of the movement varies with the TC, allowing for a quantitative display of the OV characteristics through the interference patterns. Additionally, we deduce analytically that the zeroth-order interference fringe has a linear relationship with the TC and the vertical position. These findings highlight the ability to identify the OV mode by analyzing the interference patterns produced by Young's doublet.
基金Project supported by the National Key Research and Development Program of China (Grant No. 2020YFA0710100)the National Natural Science Foundation of China (Grant Nos. 92050102 and 11874311)the Fundamental Research Funds for the Central Universities (Grant Nos. 20720220033 and 20720200074)。
文摘Super-resolution imaging with superlens has been one of the fundamental research topics. Unfortunately, the resolution of superlens is inevitably restrained by material loss. To address the problem, we introduce the solid immersion mechanism into the slab superlens and the cylindrical superlens. The proposed solid immersion slab superlens(SISSL) and the solid immersion cylindrical superlens(SICSL) can improve the resolution by converting evanescent wave to propagating wave using high refractive index materials. From the perspective of applications, the cylindrical superlens with finite cross section and the ability of magnification or demagnification has more advantages than the slab superlens. Therefore,we focus on demonstrating analytically the super-resolution imaging of SICSL. Due to the impedance mismatching caused by solid immersion mechanism, the whispering gallery modes(WGMs) are excited between SICSL and the air interface.We clarify the excitation conditions of WGMs and analyze their influence on the imaging quality of SICSL. The SISSL and SICSL may pave a way to apply in lithography technique and real-time biomolecular imaging in future.
基金Project supported by the National Key Research and Development Program of China (Grant No. 2020YFA0710100)the National Natural Science Foundation of China (Grant Nos. 92050102 and 11874311)+1 种基金the Shenzhen Science and Technology Program (Grant No. JCYJ20210324121610028)the Fundamental Research Funds for the Central Universities (Grant Nos. 20720220033 and 20720200074)。
文摘The energy crisis has aroused widespread concern, and the reform of energy structure is imminent. In the future,the energy structure will be dominated by the solar energy and other renewable energy sources. The solar concentrating technology as a promising method has been widely studied for collecting solar energy. However, the previous solar concentrating technologies suffer from some drawbacks, such as low focusing efficiency and large concentrating size. The Luneburg lens with highly efficient aberration-free focusing provides a new route for solar/energy concentrator. In this work, we designed a plane focal surface Luneburg lens(PFSLL) by transformation optics(TO). The PFSLL provides a relatively high focusing efficiency and concentration ratio of collection of energy. At the same time, it circumvents the disadvantage of curve surface of the classical Luneburg lens in device integration. Based on the reciprocity of electromagnetic waves, the PFSLL can also be applied to the antenna field to achieve broadband wide-angle scanning and highly directional radiation.
基金Supported by the National Natural Science Foundation of China under Grant No 10334020, and in part by the National Minister of Education Programme for Changjiang Scholars and Innovative Research Team in University.
文摘We present an impedance-matched reduced version of acoustic cloaking whose mass is in a reasonable range. A layered cloak design with isotropic material is also proposed for the reduced cloak. Numerical calculations from the transfer matrix methods show that the present layered cloak can reduce the scattering of an air cylinder substantially.
基金Project supported by the National Natural Science Foundation of China (Grant No. 92050102)the National Key Research and Development Program of China (Grant No. 2020YFA0710100)the Fundamental Research Funds for Central Universities, China (Grant Nos. 20720200074, 20720220134, 202006310051, and 20720220033)。
文摘Super-resolution imaging is vital for optical applications, such as high capacity information transmission, real-time bio-molecular imaging, and nanolithography. In recent years, technologies and methods of super-resolution imaging have attracted much attention. Different kinds of novel lenses, from the superlens to the super-oscillatory lens, have been designed and fabricated to break through the diffraction limit. However, the effect of the super-resolution imaging in these lenses is not satisfactory due to intrinsic loss, aberration, large sidebands, and so on. Moreover, these lenses also cannot realize multiple super-resolution imaging. In this research, we introduce the solid immersion mechanism to Mikaelian lens(ML) for multiple super-resolution imaging. The effect is robust and valid for broadband frequencies. Based on conformal transformation optics as a bridge linking the solid immersion ML and generalized Maxwell's fish-eye lens(GMFEL), we also discovered the effect of multiple super-resolution imaging in the solid immersion GMFEL.
基金National Natural Science Foundation of China(Grant No.11874311)Natural Science Foundation of Fujian Province,China(Grant No.2017J05015)。
文摘The propagation of acoustic waves is a fundamental topic in shallow ocean acoustics.We numerically demonstrate a three-dimensional zone of silence consisting of a circular tube with gradient index metamaterials attached to its rigid wall.The cloaking effect is verified by fine agreement with analytical calculations.
基金Supported by the National Natural Science Foundation of China(Grant No.11874311).
文摘We propose multi-core conformal lenses by combining conformal transformation optics with absolute instruments.Depending on the cores and incident angles,the conformal lenses have tunable functionalities like focusing,reflection,and transparency,thereby providing a feasible general method for designing multi-functional devices.
基金supported by the National Natural Science Foundation of China(Nos.92050102,11974010,and 12274313)the Fundamental Research Funds for the Central Universities(Nos.20720230102 and 20720220033)+1 种基金the National Key R&D Program of China(Nos.2020YFA0710100,2022YFA1404400,and 2022YFA1404300)the China Scholarship Council(No.202106310002).
文摘Vortex waves with orbital angular momentum(OAM)are a highly active research topic in various fields.In this paper,we design and investigate cylindrical metagratings(CMs)with an even number of unit cells that can efficiently achieve vortex localization and specific OAM selective conversion.The multifunctional manipulation of vortex waves and the new OAM conservation law have further been confirmed through analytical calculations and numerical simulations.In addition,we qualitatively and quantitatively determine the OAM range for vortex localization and the OAM value of vortex selective conversion and also explore the stability for performance and potential applications of the designed structure.This work holds potential applications in particle manipulation and optical communication.
基金supported by the National Natural Science Foundation of China(12274225,11974010,12274313,92050102,and12374410)the Natural Science Foundation of Jiangsu Province(BK20230089)+1 种基金the National Key R&D Program of China(2022YFA1404300 and 2022YFA1404400)the Fundamental Research Funds for the Central Universities(NE2022007,20720220033,and 20720230102)。
基金This work was supported by the National Natural Science Foundation of China(No.11874311).
文摘In this Letter,we find that Morse potential(proposed about 90 years ago)could be connected to Coulomb potential(or Newton potential)and harmonic potential(or Hooke potential)by conformal mappings.We thereby design a new conformal lens from Morse potential,Eaton lens,and Luneburg lens and propose a series of generalized Eaton/Luneburg lenses.We find that this Morse lens is a perfect self-focusing asymmetric lens that differs from a Mikaelian lens.Our theory provides a new insight to Morse potential and other traditional potentials,and revisits their classical applications on designing lenses.
基金supported by the National Natural Science Foundation of China(Nos.11874311 and 11504306)the Fujian Provincial Natural Science Foundation(No.2017J05015)
文摘Effective medium theory is a powerful tool to solve various problems for achieving multifarious functionalities and applications. In this article, we present a concise empirical formula about effective permittivity of checkboard structures for different directions. To verify our empirical formula, we perform simulations of checkboard periodic structures in squares, rectangles, and sectors in two dimensions. Our results show that the formula is valid in a large range of parameters. This work provides a new way to understand and design composite materials, which might lead to further optical applications in transformation optics.
基金Acknowledgements The authors thank Prof. Shengwang Du for the useful discussions. This work was supported by the National Natural Science Foundation of China （Grant No. 11004147） and the Key project in Science and Technology Innovation Program of Sooehow University.
文摘An illusion counter-part displays the same scattering far-field pattern as that of a real object. In this paper, for the first time, we demonstrate that such an unreal illusion can be cloaked by an external cloak. This phenomenon shall be called ＂cloak an illusion＂. Numerical simulations were performed to demonstrate such a phenomenon.
基金the National Natural Science Foundation of China(92050102)the National Key Research and Development Program of China(2020YFA0710100)+1 种基金the National Natural Science Foundation of China(11874311)the FundamentalResearch Funds for the Central Universities(20720200074 and20720190049)。
基金supported by the National Key Research and Development Program of China (No. 2020YFA0710100)the National Science Foundation of China (Nos. 11874311 and 92050102)the Fundamental Research Funds for the Central Universities (No. 20720200074)
文摘It is well known that cats have fascinating eyes with various colors,such as green,blue,and brown.In addition,they possess strong night vision ability,which can distinguish things clearly even in a poor light environment.These drive us to reveal the secrets behind them.In fact,cats’ eyes can be considered as special lenses(which we would like to mimic by using a Luneburg lens).We make an analysis of the role of photonic crystals behind the lens and demonstrate that the integration of photonic crystals into Luneburg lens can be regarded as a retroreflector and greatly improve the light focusing intensity of the lens in a broad band of frequencies.This wonderful bioinspired phenomenon is expected to design more interesting and serviceable devices by combining photonic crystals with transformation optics.
