Lenses are crucial to light-enabled technologies.Conventional lenses have been perfected to achieve near-diffraction-limited resolution and minimal chromatic aberrations.However,such lenses are bulky and cannot focus ...Lenses are crucial to light-enabled technologies.Conventional lenses have been perfected to achieve near-diffraction-limited resolution and minimal chromatic aberrations.However,such lenses are bulky and cannot focus light into a hotspot smaller than a half-wavelength of light.Pupil filters,initially suggested by Toraldo di Francia,can overcome the resolution constraints of conventional lenses but are not intrinsically chromatically corrected.Here we report single-element planar lenses that not only deliver sub-wavelength focusing,thus beating the diffraction limit of conventional refractive lenses,but also focus light of different colors into the same hotspot.Using the principle of super-oscillations,we designed and fabricated a range of binary dielectric and metallic lenses for visible and infrared parts of the spectrum that are manufactured on silicon wafers,silica substrates and optical fiber tips.Such low-cost,compact lenses could be useful in mobile devices,data storage,surveillance,robotics,space applications,imaging,manufacturing with light and spatially resolved nonlinear microscopies.展开更多
The ability to control the wavefront of light is fundamental to focusing and redistribution of light,enabling many applications from imaging to spectroscopy.Wave interaction on highly nonlinear photorefractive materia...The ability to control the wavefront of light is fundamental to focusing and redistribution of light,enabling many applications from imaging to spectroscopy.Wave interaction on highly nonlinear photorefractive materials is essentially the only established technology allowing the dynamic control of the wavefront of a light beam with another beam of light,but it is slow and requires large optical power.Here we report a proof-of-principle demonstration of a new technology for two-dimensional(2D)control of light with light based on the coherent interaction of optical beams on highly absorbing plasmonic metasurfaces.We illustrate this by performing 2D all-optical logical operations(AND,XOR and OR)and image processing.Our approach offers diffractionlimited resolution,potentially at arbitrarily-low intensity levels and with 100 THz bandwidth,thus promising new applications in space-division multiplexing,adaptive optics,image correction,processing and recognition,2D binary optical data processing and reconfigurable optical devices.展开更多
Super-oscillation is a counterintuitive phenomenon describing localized fast variations of functions and fields that happen at frequencies higher than the highest Fourier component of their spectra.The physical implic...Super-oscillation is a counterintuitive phenomenon describing localized fast variations of functions and fields that happen at frequencies higher than the highest Fourier component of their spectra.The physical implications of this effect have been studied in information theory and optics of classical fields,and have been used in super-resolution imaging.As a general phenomenon of wave dynamics,super-oscillations have also been predicted to exist in quantum wavefunctions.Here we report the experimental demonstration of super-oscillatory behavior of a single-quantum object,a photon.The super-oscillatory behavior is demonstrated by tight localization of the photon wavefunction after focusing with an appropriately designed slit mask to create an interference pattern with a sub-diffraction hotspot(~0.45λ).Such quantum super-oscillation can be used for low-intensity far-field super-resolution imaging techniques even down to single-photon counting regime,which would be of interest to quantum physics and non-invasive and label-free biological studies.展开更多
Vision,microscopy,imaging,optical data projection and storage all depend on focusing of light.Dynamic focusing is conventionally achieved with mechanically reconfigurable lenses,spatial light modulators or microfluidi...Vision,microscopy,imaging,optical data projection and storage all depend on focusing of light.Dynamic focusing is conventionally achieved with mechanically reconfigurable lenses,spatial light modulators or microfluidics.Here we demonstrate that dynamic control of focusing can be achieved through coherent interaction of optical waves on a thin beam splitter.We use a nanostructured plasmonic metasurface of subwavelength thickness as the beam splitter,allowing operation in the regimes of coherent absorption and coherent transparency.Focusing of light resulting from illumination of the plasmonic metasurface with a Fresnel zone pattern is controlled by another patterned beam projected on the same metasurface.By altering the control pattern,its phase,or its intensity,we switch the lens function on and off,and alter the focal spot’s depth,diameter and intensity.Switching occurs as fast as the control beam is modulated and therefore tens of gigahertz modulation bandwidth is possible with electro-optical modulators,which is orders of magnitude faster than conventional dynamic focusing technologies.展开更多
基金supported by the Agency for Science,Technology and Research(A*STAR)of Singapore(Grants 122-360-0009)the Singapore Ministry of Education(Grant MOE2011-T3-1-005)+1 种基金the Engineering and Physical Sciences Research Council UK(Grants EP/F040644/1 and EP/M009122/1)the University of Southampton Enterprise Fund.
文摘Lenses are crucial to light-enabled technologies.Conventional lenses have been perfected to achieve near-diffraction-limited resolution and minimal chromatic aberrations.However,such lenses are bulky and cannot focus light into a hotspot smaller than a half-wavelength of light.Pupil filters,initially suggested by Toraldo di Francia,can overcome the resolution constraints of conventional lenses but are not intrinsically chromatically corrected.Here we report single-element planar lenses that not only deliver sub-wavelength focusing,thus beating the diffraction limit of conventional refractive lenses,but also focus light of different colors into the same hotspot.Using the principle of super-oscillations,we designed and fabricated a range of binary dielectric and metallic lenses for visible and infrared parts of the spectrum that are manufactured on silicon wafers,silica substrates and optical fiber tips.Such low-cost,compact lenses could be useful in mobile devices,data storage,surveillance,robotics,space applications,imaging,manufacturing with light and spatially resolved nonlinear microscopies.
基金supported by the UK’s Defence Science and Technology Laboratory(Grant DSTLX1000064081)the MOE Singapore(Grant MOE2011-T3-1-005)+2 种基金the Leverhulme Trustthe University of Southampton Enterprise Fundthe UK’s Engineering and Physical Sciences Research Council(Grant EP/G060363/1)。
文摘The ability to control the wavefront of light is fundamental to focusing and redistribution of light,enabling many applications from imaging to spectroscopy.Wave interaction on highly nonlinear photorefractive materials is essentially the only established technology allowing the dynamic control of the wavefront of a light beam with another beam of light,but it is slow and requires large optical power.Here we report a proof-of-principle demonstration of a new technology for two-dimensional(2D)control of light with light based on the coherent interaction of optical beams on highly absorbing plasmonic metasurfaces.We illustrate this by performing 2D all-optical logical operations(AND,XOR and OR)and image processing.Our approach offers diffractionlimited resolution,potentially at arbitrarily-low intensity levels and with 100 THz bandwidth,thus promising new applications in space-division multiplexing,adaptive optics,image correction,processing and recognition,2D binary optical data processing and reconfigurable optical devices.
基金support from the Advanced Optics in Engineering Programme from the Agency for Science,Technology and Research of Singapore with grant number 122-360-0009Singapore Ministry of Education Academic Research Fund Tier 3 with grant number MOE2011-T3-1-005+2 种基金the UK Engineering and Physical Sciences Research Council with grant numbers EP/F040644/1 and EP/M009122/1the Royal Society of London and the University of Southampton Enterprise Fundfunding of the Labex ACTION program(contract no.ANR-11-LABX-0001-01).
文摘Super-oscillation is a counterintuitive phenomenon describing localized fast variations of functions and fields that happen at frequencies higher than the highest Fourier component of their spectra.The physical implications of this effect have been studied in information theory and optics of classical fields,and have been used in super-resolution imaging.As a general phenomenon of wave dynamics,super-oscillations have also been predicted to exist in quantum wavefunctions.Here we report the experimental demonstration of super-oscillatory behavior of a single-quantum object,a photon.The super-oscillatory behavior is demonstrated by tight localization of the photon wavefunction after focusing with an appropriately designed slit mask to create an interference pattern with a sub-diffraction hotspot(~0.45λ).Such quantum super-oscillation can be used for low-intensity far-field super-resolution imaging techniques even down to single-photon counting regime,which would be of interest to quantum physics and non-invasive and label-free biological studies.
基金supported by the University of Southampton Enterprise Fund,the UK's Engineering and Physical Sciences Research Council(grant EP/M009122/1)the MOE Singapore(grant MOE2011-T3-1-005)。
文摘Vision,microscopy,imaging,optical data projection and storage all depend on focusing of light.Dynamic focusing is conventionally achieved with mechanically reconfigurable lenses,spatial light modulators or microfluidics.Here we demonstrate that dynamic control of focusing can be achieved through coherent interaction of optical waves on a thin beam splitter.We use a nanostructured plasmonic metasurface of subwavelength thickness as the beam splitter,allowing operation in the regimes of coherent absorption and coherent transparency.Focusing of light resulting from illumination of the plasmonic metasurface with a Fresnel zone pattern is controlled by another patterned beam projected on the same metasurface.By altering the control pattern,its phase,or its intensity,we switch the lens function on and off,and alter the focal spot’s depth,diameter and intensity.Switching occurs as fast as the control beam is modulated and therefore tens of gigahertz modulation bandwidth is possible with electro-optical modulators,which is orders of magnitude faster than conventional dynamic focusing technologies.