The colour gamut,a two-dimensional(2D)colour space primarily comprising hue and saturation(HS),lays the most important foundation for the colour display and printing industries.Recently,the metasurface has been consid...The colour gamut,a two-dimensional(2D)colour space primarily comprising hue and saturation(HS),lays the most important foundation for the colour display and printing industries.Recently,the metasurface has been considered a promising paradigm for nanoprinting and holographic imaging,demonstrating a subwavelength image resolution,a flat profile,high durability,and multi-functionalities.Much effort has been devoted to broaden the 2D HS plane,also known as the CIE map.However,the brightness(B),as the carrier of chiaroscuro information,has long been neglected in metasurface-based nanoprinting or holograms due to the challenge in realising arbitrary and simultaneous control of full-colour HSB tuning in a passive device.Here,we report a dielectric metasurface made of crystal silicon nanoblocks,which achieves not only tailorable coverage of the primary colours red,green and blue(RGB)but also intensity control of the individual colours.The colour gamut is hence extruded from the 2D CIE to a complete 3D HSB space.Moreover,thanks to the independent control of the RGB intensity and phase,we further show that a singlelayer silicon metasurface could simultaneously exhibit arbitrary HSB colour nanoprinting and a full-colour hologram image.Our findings open up possibilities for high-resolution and high-fidelity optical security devices as well as advanced cryptographic approaches.展开更多
High salt is a major environmental factor that threatens plant growth and development.Increasing evidence indicates that histone acetylation is involved in plant responses to various abiotic stress;however,the underly...High salt is a major environmental factor that threatens plant growth and development.Increasing evidence indicates that histone acetylation is involved in plant responses to various abiotic stress;however,the underlying epigenetic regulatory mechanisms remain poorly understood.In this study,we revealed that the histone deacetylase OsHDA706 epigenetically regulates the expression of salt stress response genes in rice(Oryza sativa L.).OsHDA706 localizes to the nucleus and cytoplasm and OsHDA706 expression is significantly induced under salt stress.Moreover,oshda706 mutants showed a higher sensitivity to salt stress than the wild-type.In vivo and in vitro enzymatic activity assays demonstrated that OsHDA706 specifically regulates the deacetylation of lysines 5 and 8 on histone H4(H4K5and H4K8).By combining chromatin immunoprecipitation and mRNA sequencing,we identified the clade A protein phosphatase 2C gene,OsPP2C49,which is involved in the salt response as a direct target of H4K5 and H4K8 acetylation.We found that the expression of OsPP2C49 is induced in the oshda706 mutant under salt stress.Furthermore,the knockout of OsPP2C49 enhances plant tolerance to salt stress,while its overexpression has the opposite effect.Taken together,our results indicate that OsHDA706,a histone H4 deacetylase,participates in the salt stress response by regulating the expression of OsPP2C49 via H4K5 and H4K8 deacetylation.展开更多
The progress of metaoptics relies on identifying photonic materials and geometries,the combination of which represents a promising approach to complex and desired optical functionalities.Material candidate options are...The progress of metaoptics relies on identifying photonic materials and geometries,the combination of which represents a promising approach to complex and desired optical functionalities.Material candidate options are primarily limited by natural availability.Thus,the search for meta-atom geometries,by either forward or inverse means,plays a pivotal role in achieving more sophisticated phenomena.Past efforts mainly focused on building the geometric library of individual meta-atoms and synthesizing various ones into a design.However,those efforts neglected the powerfulness of perturbative metaoptics due to the perception that perturbations are usually regarded as adverse and in need of being suppressed.Here,we report a perturbation-induced countersurveillance strategy using compound nanosieves mediated by structural and thermal perturbations.Private information can be almost perfectly concealed and camouflaged by the induced thermal-spectral drifts,enabling information storage and exchange in a covert way.This perturbative metaoptics can self-indicate whether the hidden information has been attacked during delivery.Our results establish a perturbative paradigm of securing a safer world of information and internet of things.展开更多
The growing demand for tailored nonlinearity calls for a structure with unusual phase discontinuity that allows the realization of nonlinear optical chirality,holographic imaging,and nonlinear wavefront control.Transi...The growing demand for tailored nonlinearity calls for a structure with unusual phase discontinuity that allows the realization of nonlinear optical chirality,holographic imaging,and nonlinear wavefront control.Transition-metal dichalcogenide(TMDC)monolayers offer giant optical nonlinearity within a few-angstrom thickness,but limitations in optical absorption and domain size impose restriction on wavefront control of nonlinear emissions using classical light sources.In contrast,noble metal-based plasmonic nanosieves support giant field enhancements and precise nonlinear phase control,with hundred-nanometer pixellevel resolution;however,they suffer from intrinsically weak nonlinear susceptibility.Here,we report a multifunctional nonlinear interface by integrating TMDC monolayers with plasmonic nanosieves,yielding drastically different nonlinear functionalities that cannot be accessed by either constituent.Such a hybrid nonlinear interface allows second-harmonic(SH)orbital angular momentum(OAM)generation,beam steering,versatile polarization control,and holograms,with an effective SH nonlinearityχ^((2))of~25 nm/V.This designer platform synergizes the TMDC monolayer and plasmonic nanosieves to empower tunable geometric phases and large field enhancement,paving the way toward multifunctional and ultracompact nonlinear optical devices.展开更多
Magnetic dipole（MD） transitions are important for a range of technologies from quantum light sources and displays to lasers and bio-probes. However, the typical MD transitions are much weaker than their electric cou...Magnetic dipole（MD） transitions are important for a range of technologies from quantum light sources and displays to lasers and bio-probes. However, the typical MD transitions are much weaker than their electric counterparts and are usually neglected in practical applications. Herein, we experimentally demonstrate that the MD transitions can be significantly enhanced by the well-developed magnetic metamaterials in the visible optical range. The magnetic metamaterials consist of silver nanostrips and a thick silver film, which are separated with an Eu3＋：polymethyl methacrylate（PMMA） film. By controlling the thickness of the Eu3＋：PMMA film, the magnetic resonance has been tuned to match the emission wavelength of MDs. Consequently,the intensity of MD emission has been significantly increased by around 30 times at the magnetic resonance wavelength, whereas the intensity of electric dipole emission is well-preserved. The corresponding numerical calculations reveal that the enhancement is directly generated by the magnetic resonance, which strongly increases the magnetic local density of states around the MD emitter and can efficiently radiate the MD emission into the far field. This is the first demonstration, to the best of our knowledge, that MD transitions can be improved by an additional degree of magnetic freedom, and we believe this research shall pave a new route towards bright magnetic emitters and their potential applications.展开更多
基金This work was supported in part by the National Key R&D Programme of China(2016YFA0301300)the Key R&D Programme of Guangdong Province(Grant No.2018B030329001)+8 种基金the National Natural Science Foundation of China(11804407,61675237,91750207,11761141015,11761131001,11674402)the Guangdong Natural Science Foundation(2016A030312012,2018A030313333)the Guangdong Natural Science Funds for Distinguished Young Scholars(2017B030306007)the Guangzhou Science and Technology Projects(201805010004)the Pearl River S&T Nova Programme of Guangzhou(201806010033)the Guangdong Special Support Programme(2017TQ04C487)the National Research Foundation Singapore and the National Natural Science Foundation of China(NSFC)Joint Grant NRF2017NRFNSFC002-015the fundamental research funds for the central universities(19lgpy262)the National Supercomputer Center in Guangzhou.C.-W.Q.acknowledges the financial support from the National Research Foundation,Prime Minister's Office,Singapore under its Competitive Research Programme(CRP award NRF CRP15-2015-03).
文摘The colour gamut,a two-dimensional(2D)colour space primarily comprising hue and saturation(HS),lays the most important foundation for the colour display and printing industries.Recently,the metasurface has been considered a promising paradigm for nanoprinting and holographic imaging,demonstrating a subwavelength image resolution,a flat profile,high durability,and multi-functionalities.Much effort has been devoted to broaden the 2D HS plane,also known as the CIE map.However,the brightness(B),as the carrier of chiaroscuro information,has long been neglected in metasurface-based nanoprinting or holograms due to the challenge in realising arbitrary and simultaneous control of full-colour HSB tuning in a passive device.Here,we report a dielectric metasurface made of crystal silicon nanoblocks,which achieves not only tailorable coverage of the primary colours red,green and blue(RGB)but also intensity control of the individual colours.The colour gamut is hence extruded from the 2D CIE to a complete 3D HSB space.Moreover,thanks to the independent control of the RGB intensity and phase,we further show that a singlelayer silicon metasurface could simultaneously exhibit arbitrary HSB colour nanoprinting and a full-colour hologram image.Our findings open up possibilities for high-resolution and high-fidelity optical security devices as well as advanced cryptographic approaches.
基金supported by grants from the National Natural Science Foundation of China(31871232)the Jiangsu Province Government(JBGS[2021]001)+3 种基金the Natural Science Foundation of Jiangsu Province(BK20200947)the State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources(SKLCUSA-b202003)the Project of Zhongshan Biological Breeding Laboratory(BM2022008-02)the Fund of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘High salt is a major environmental factor that threatens plant growth and development.Increasing evidence indicates that histone acetylation is involved in plant responses to various abiotic stress;however,the underlying epigenetic regulatory mechanisms remain poorly understood.In this study,we revealed that the histone deacetylase OsHDA706 epigenetically regulates the expression of salt stress response genes in rice(Oryza sativa L.).OsHDA706 localizes to the nucleus and cytoplasm and OsHDA706 expression is significantly induced under salt stress.Moreover,oshda706 mutants showed a higher sensitivity to salt stress than the wild-type.In vivo and in vitro enzymatic activity assays demonstrated that OsHDA706 specifically regulates the deacetylation of lysines 5 and 8 on histone H4(H4K5and H4K8).By combining chromatin immunoprecipitation and mRNA sequencing,we identified the clade A protein phosphatase 2C gene,OsPP2C49,which is involved in the salt response as a direct target of H4K5 and H4K8 acetylation.We found that the expression of OsPP2C49 is induced in the oshda706 mutant under salt stress.Furthermore,the knockout of OsPP2C49 enhances plant tolerance to salt stress,while its overexpression has the opposite effect.Taken together,our results indicate that OsHDA706,a histone H4 deacetylase,participates in the salt stress response by regulating the expression of OsPP2C49 via H4K5 and H4K8 deacetylation.
基金supported in part by the National Key R&D Program of China(2016YFA0301300)the Key R&D Program of Guangdong Province(Grant No.2018B030329001)+8 种基金the National Natural Science Foundation of China(61675237,11761141015,91750207)the Guangdong Natural Science Funds for Distinguished Young Scholars(2017B030306007)the Guangdong Special Support Program(2017TQ04C487)the Guangdong Natural Science Foundation(2016A030312012)the Pearl River S&T Nova Program of Guangzhou(201806010033)the Guangzhou Science and Technology Project(201805010004)the National Research Foundation Singaporethe National Natural Science Foundation of China(NSFC)Joint Grant NRF2017NRFNSFC002-015partially supported by the National Research Foundation,Prime Minister’s Office,Singapore,under its Competitive Research Programme(CRP award no.NRF-CRP15-2015-03).
文摘The progress of metaoptics relies on identifying photonic materials and geometries,the combination of which represents a promising approach to complex and desired optical functionalities.Material candidate options are primarily limited by natural availability.Thus,the search for meta-atom geometries,by either forward or inverse means,plays a pivotal role in achieving more sophisticated phenomena.Past efforts mainly focused on building the geometric library of individual meta-atoms and synthesizing various ones into a design.However,those efforts neglected the powerfulness of perturbative metaoptics due to the perception that perturbations are usually regarded as adverse and in need of being suppressed.Here,we report a perturbation-induced countersurveillance strategy using compound nanosieves mediated by structural and thermal perturbations.Private information can be almost perfectly concealed and camouflaged by the induced thermal-spectral drifts,enabling information storage and exchange in a covert way.This perturbative metaoptics can self-indicate whether the hidden information has been attacked during delivery.Our results establish a perturbative paradigm of securing a safer world of information and internet of things.
基金This work was supported by the National Natural Science Foundation of China(nos.91850113 and 11774115)the 973 Programs under grant 2014CB921301+3 种基金the Fundamental Research Funds for the Central Universities(2019kfyRCPY105)the Air Force Office of Scientific Research,and the Defense Advanced Research Projects AgencyC.-W.Q.acknowledges financial support from A*STAR Pharos Program(grant number 1527000014,with project number R-263-000-B91-305)the National Research Foundation,Prime Minister’s Office,Singapore,under its Competitive Research Program(CRP award number NRFCRP 15-2015-03).
文摘The growing demand for tailored nonlinearity calls for a structure with unusual phase discontinuity that allows the realization of nonlinear optical chirality,holographic imaging,and nonlinear wavefront control.Transition-metal dichalcogenide(TMDC)monolayers offer giant optical nonlinearity within a few-angstrom thickness,but limitations in optical absorption and domain size impose restriction on wavefront control of nonlinear emissions using classical light sources.In contrast,noble metal-based plasmonic nanosieves support giant field enhancements and precise nonlinear phase control,with hundred-nanometer pixellevel resolution;however,they suffer from intrinsically weak nonlinear susceptibility.Here,we report a multifunctional nonlinear interface by integrating TMDC monolayers with plasmonic nanosieves,yielding drastically different nonlinear functionalities that cannot be accessed by either constituent.Such a hybrid nonlinear interface allows second-harmonic(SH)orbital angular momentum(OAM)generation,beam steering,versatile polarization control,and holograms,with an effective SH nonlinearityχ^((2))of~25 nm/V.This designer platform synergizes the TMDC monolayer and plasmonic nanosieves to empower tunable geometric phases and large field enhancement,paving the way toward multifunctional and ultracompact nonlinear optical devices.
基金the National Natural Science Foundation of China (No. 11374078)the Shenzhen Fundamental Research Projects (Nos. JCYJ20160301154309393, JCYJ20160505175637639, and JCYJ2016042718325 9083)+1 种基金the Public Platform for Fabrication and Detection of Micro- & Nano-Sized Aerospace Devicesthe Shenzhen Engineering Laboratory on Onganic-Inorganic Perovskite Devices for financial support
文摘Magnetic dipole（MD） transitions are important for a range of technologies from quantum light sources and displays to lasers and bio-probes. However, the typical MD transitions are much weaker than their electric counterparts and are usually neglected in practical applications. Herein, we experimentally demonstrate that the MD transitions can be significantly enhanced by the well-developed magnetic metamaterials in the visible optical range. The magnetic metamaterials consist of silver nanostrips and a thick silver film, which are separated with an Eu3＋：polymethyl methacrylate（PMMA） film. By controlling the thickness of the Eu3＋：PMMA film, the magnetic resonance has been tuned to match the emission wavelength of MDs. Consequently,the intensity of MD emission has been significantly increased by around 30 times at the magnetic resonance wavelength, whereas the intensity of electric dipole emission is well-preserved. The corresponding numerical calculations reveal that the enhancement is directly generated by the magnetic resonance, which strongly increases the magnetic local density of states around the MD emitter and can efficiently radiate the MD emission into the far field. This is the first demonstration, to the best of our knowledge, that MD transitions can be improved by an additional degree of magnetic freedom, and we believe this research shall pave a new route towards bright magnetic emitters and their potential applications.
