The Brewster reflectionless effect stands out as one of the simplest yet pivotal discoveries in manipulating waves[1,2].Initial investigations were limited to isotropic materials,but later,thanks to the advent of meta...The Brewster reflectionless effect stands out as one of the simplest yet pivotal discoveries in manipulating waves[1,2].Initial investigations were limited to isotropic materials,but later,thanks to the advent of metamaterials,the phenomenon was found to expand into anisotropic materials.An anomalous Brewster effect has been recently demonstrated in metamaterials with rotation angle,thus increasing the number of degrees of freedom[3].In materials without magnetic responses,the Brewster effect exclusively applies to transverse-magnetic(TM,or p-wave polarization)waves[4].展开更多
Hyperbolic shear polaritons(HShPs)emerge with widespread attention as a class of polariton modes with broken symmetry due to shear lattices.We find a mechanism of generating quasi-HShPs(q-HShPs).When utilizing vortex ...Hyperbolic shear polaritons(HShPs)emerge with widespread attention as a class of polariton modes with broken symmetry due to shear lattices.We find a mechanism of generating quasi-HShPs(q-HShPs).When utilizing vortex waves as excitation sources of hyperbolic materials without off-diagonal elements,q-HShPs will appear.In addition,these asymmetric q-HShPs can be recovered as symmetric modes away from the source,with a critical transition mode between the left-skewed and right-skewed q-HShPs,via tuning the magnitude of the off-diagonal imaginary component and controlling the topological charge of the vortex source.It is worth mentioning that we explore the influence of parity of topological charges on the field distribution and demonstrate these exotic phenomena from numerical and analytical perspectives.Our results will promote opportunities for both q-HShPs and vortex waves,widening the horizon for various hyperbolic materials based on vortex sources and offering a degree of freedom to control various kinds of polaritons.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supported by the National Natural Science Foundation of China(12361161667 and 12374410)National Key Research and Development Program of China(2023YFA1407100 and 2020YFA0710100)the China Scholarship Council(202206310008)。
文摘The Brewster reflectionless effect stands out as one of the simplest yet pivotal discoveries in manipulating waves[1,2].Initial investigations were limited to isotropic materials,but later,thanks to the advent of metamaterials,the phenomenon was found to expand into anisotropic materials.An anomalous Brewster effect has been recently demonstrated in metamaterials with rotation angle,thus increasing the number of degrees of freedom[3].In materials without magnetic responses,the Brewster effect exclusively applies to transverse-magnetic(TM,or p-wave polarization)waves[4].
基金supported by the National Natural Science Foundation of China(Grant Nos.92050102 and 11904006)The National Key Research and Development Program of China(Grant No.2020YFA0710100)+2 种基金Jiangxi Provincial Natural Science Foundation(Grant Nos.20224ACB201005)Shenzhen Science and Technology Program(Grant Nos.JCYJ20210324121610028)the Fundamental Research Funds for the Central Universities(Grant Nos.20720200074,20720220134,and 20720220033).
文摘Hyperbolic shear polaritons(HShPs)emerge with widespread attention as a class of polariton modes with broken symmetry due to shear lattices.We find a mechanism of generating quasi-HShPs(q-HShPs).When utilizing vortex waves as excitation sources of hyperbolic materials without off-diagonal elements,q-HShPs will appear.In addition,these asymmetric q-HShPs can be recovered as symmetric modes away from the source,with a critical transition mode between the left-skewed and right-skewed q-HShPs,via tuning the magnitude of the off-diagonal imaginary component and controlling the topological charge of the vortex source.It is worth mentioning that we explore the influence of parity of topological charges on the field distribution and demonstrate these exotic phenomena from numerical and analytical perspectives.Our results will promote opportunities for both q-HShPs and vortex waves,widening the horizon for various hyperbolic materials based on vortex sources and offering a degree of freedom to control various kinds of polaritons.
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.
