Electrically connected optical metasurfaces with high efficiencies are crucial for developing spatiotemporal metadevices with ultrahigh spatial and ultrafast temporal resolutions.While efficient metal–insulator–meta...Electrically connected optical metasurfaces with high efficiencies are crucial for developing spatiotemporal metadevices with ultrahigh spatial and ultrafast temporal resolutions.While efficient metal–insulator–metal(MIM)metasurfaces containing discretized meta-atoms require additional electrodes,Babinet-inspired slot-antenna-based plasmonic metasurfaces suffer from low efficiencies and limited phase coverage for copolarized optical fields.Capitalizing on the concepts of conventional MIM and slot-antenna metasurfaces,we design and experimentally demonstrate a new type of optical reflective metasurfaces consisting of mirrorcoupled slot antennas(MCSAs).By tuning the dimensions of rectangular-shaped nanoapertures atop a dielectric-coated gold mirror,we achieve efficient phase modulation within a sufficiently large range of 320 deg and realize functional phase-gradient metadevices for beam steering and beam splitting in the near-infrared range.The fabricated samples show(22%2%)diffraction efficiency for beam steering and(17%1%)for beam splitting at the wavelength of 790 nm.The considered MCSA configuration,dispensing with auxiliary electrodes,offers an alternative and promising platform for electrically controlled reflective spatiotemporal metasurfaces.展开更多
A fundamental challenge in endoscopy is how to fabricate a small fiber-optic probe that can achieve comparable function to devices with large,complicated optics.To achieve high resolution over an extended depth of foc...A fundamental challenge in endoscopy is how to fabricate a small fiber-optic probe that can achieve comparable function to devices with large,complicated optics.To achieve high resolution over an extended depth of focus(DOF),the application of needle-like beams has been proposed.However,existing methods for miniaturized needle-beam designs fail to adequately correct astigmatism and other monochromatic aberrations,limiting the resolution of at least one axis.Here,we describe an approach to realize freeform beam-shaping endoscopic probes via two-photon polymerization three-dimensional(3D)printing.We present a design achieving<8μm lateral resolution with a DOF of∼800μm.The probe has a diameter of<260μm(without the torque coil and catheters)and is fabricated using a single printing step directly on the optical fiber.The probe was successfully utilized for intravascular imaging in living diabetic swine at multiple time points,as well as human atherosclerotic plaques ex vivo.To the best of our knowledge,this is the first report of a 3D-printed micro-optic for in vivo imaging of the coronary arteries.These results are a substantial step to enable the clinical adoption of both 3D-printed micro-optics and beam-tailoring devices.展开更多
Compact nanophotonic elements exhibiting adaptable properties are essential components for the miniaturization of powerful optical technologies such as adaptive optics and spatial light modulators.While the larger cou...Compact nanophotonic elements exhibiting adaptable properties are essential components for the miniaturization of powerful optical technologies such as adaptive optics and spatial light modulators.While the larger counterparts typically rely on mechanical actuation,this can be undesirable in some cases on a microscopic scale due to inherent space restrictions.Here,we present a novel design concept for highly integrated active optical components that employs a combination of resonant plasmonic metasurfaces and the phase-change material Ge3Sb2Te6.In particular,we demonstrate beam switching and bifocal lensing,thus,paving the way for a plethora of active optical elements employing plasmonic metasurfaces,which follow the same design principles.展开更多
Preclinical and clinical diagnostics increasingly rely on techniques to visualize internal organs at high resolution via endoscopes.Miniaturized endoscopic probes are necessary for imaging small luminal or delicate or...Preclinical and clinical diagnostics increasingly rely on techniques to visualize internal organs at high resolution via endoscopes.Miniaturized endoscopic probes are necessary for imaging small luminal or delicate organs without causing trauma to tissue.However,current fabrication methods limit the imaging performance of highly miniaturized probes,restricting their widespread application.To overcome this limitation,we developed a novel ultrathin probe fabrication technique that utilizes 3D microprinting to reliably create side-facing freeform micro-optics(<130μm diameter)on single-mode fibers.Using this technique,we built a fully functional ultrathin aberration-corrected optical coherence tomography probe.This is the smallest freeform 3D imaging probe yet reported,with a diameter of 0.457 mm,including the catheter sheath.We demonstrated image quality and mechanical flexibility by imaging atherosclerotic human and mouse arteries.The ability to provide microstructural information with the smallest optical coherence tomography catheter opens a gateway for novel minimally invasive applications in disease.展开更多
Manipulating light on the nanoscale has become a central challenge in metadevices,resonant surfaces,nanoscale optical sensors,and many more,and it is largely based on resonant light confinement in dispersive and lossy...Manipulating light on the nanoscale has become a central challenge in metadevices,resonant surfaces,nanoscale optical sensors,and many more,and it is largely based on resonant light confinement in dispersive and lossy metals and dielectrics.Here,we experimentally implement a novel strategy for dielectric nanophotonics:Resonant subwavelength localized confinement of light in air.We demonstrate that voids created in high-index dielectric host materials support localized resonant modes with exceptional optical properties.Due to the confinement in air,the modes do not suffer from the loss and dispersion of the dielectric host medium.We experimentally realize these resonant Mie voids by focused ion beam milling into bulk silicon wafers and experimentally demonstrate resonant light confinement down to the UV spectral range at 265 nm(4.68 eV).Furthermore,we utilize the bright,intense,and naturalistic colours for nanoscale colour printing.Mie voids will thus push the operation of functional high-index metasurfaces into the blue and UV spectral range.The combination of resonant dielectric Mie voids with dielectric nanoparticles will more than double the parameter space for the future design of metasurfaces and other micro-and nanoscale optical elements.In particular,this extension will enable novel antenna and structure designs which benefit from the full access to the modal field inside the void as well as the nearly free choice of the high-index material for novel sensing and active manipulation strategies.展开更多
We experimentally demonstrate an ultra-thin plasmonic optical rotator in the visible regime that induces a polarization rotation that is continuously tunable and switchable by an external magnetic field.The rotator is...We experimentally demonstrate an ultra-thin plasmonic optical rotator in the visible regime that induces a polarization rotation that is continuously tunable and switchable by an external magnetic field.The rotator is a magneto-plasmonic hybrid structure consisting of a magneto-optical EuSe slab and a one-dimensional plasmonic gold grating.At low temperatures,EuSe possesses a large Verdet constant and exhibits Faraday rotation,which does not saturate over a regime of several Tesla.By combining these properties with plasmonic Faraday rotation enhancement,a large tuning range of the polarization rotation of up to 8.4° for a film thickness of 220 nm is achieved.Furthermore,through experiments and simulations,we demonstrate that the unique dispersion properties of the structure enable us to tailor the wavelengths of the tunable polarization rotation to arbitrary spectral positions within the transparency window of the magneto-optical slab.The demonstrated concept might lead to important,highly integrated,non-reciprocal,photonic devices for light modulation,optical isolation,and magnetic field optical sensing.The simple fabrication of EuSe nanostructures by physical vapor deposition opens the way for many potentially interesting magneto-plasmonic systems and three-dimensional magneto-optical metamaterials.展开更多
Nanophotonic platforms such as metasurfaces,achieving arbitrary phase profiles within ultrathin thickness,emerge as miniaturized,ultracompact and kaleidoscopic optical vortex generators.However,it is often required to...Nanophotonic platforms such as metasurfaces,achieving arbitrary phase profiles within ultrathin thickness,emerge as miniaturized,ultracompact and kaleidoscopic optical vortex generators.However,it is often required to segment or interleave independent sub-array metasurfaces to multiplex optical vortices in a single nano-device,which in turn affects the device’s compactness and channel capacity.Here,inspired by phyllotaxis patterns in pine cones and sunflowers,we theoretically prove and experimentally report that multiple optical vortices can be produced in a single compact phyllotaxis nanosieve,both in free space and on a chip,where one meta-atom may contribute to many vortices simultaneously.The time-resolved dynamics of on-chip interference wavefronts between multiple plasmonic vortices was revealed by ultrafast time-resolved photoemission electron microscopy.Our nature-inspired optical vortex generator would facilitate various vortex-related optical applications,including structured wavefront shaping,free-space and plasmonic vortices,and high-capacity information metaphotonics.展开更多
We present a fully automated laser system with low-intensity noise for coherent Raman scattering microscopy.The robust two-color system is pumped by a solid-state oscillator,which provides Stokes pulses fixed at 1043 ...We present a fully automated laser system with low-intensity noise for coherent Raman scattering microscopy.The robust two-color system is pumped by a solid-state oscillator,which provides Stokes pulses fixed at 1043 nm.The tunable pump pulses of 750 to 950 nm are generated by a frequency-doubled fiberfeedback femtosecond optical parametric oscillator.The resulting pulse duration of 1.2 ps provides a viable compromise between optimal coherent Raman scattering signal and the necessary spectral resolution.Thus a spectral range of 1015 to 3695 cm−1 with spectral resolution of<13 cm−1 can be addressed.展开更多
The miniaturisation of spectroscopic measurement devices opens novel information channels for size critical applications such as endoscopy or consumer electronics.Computational spectrometers in the micrometre size ran...The miniaturisation of spectroscopic measurement devices opens novel information channels for size critical applications such as endoscopy or consumer electronics.Computational spectrometers in the micrometre size range have been demonstrated,however,these are calibration sensitive and based on complex reconstruction algorithms.Herein we present an angle-insensitive 3D-printed miniature spectrometer with a direct separated spatial-spectral response.The spectrometer was fabricated via two-photon direct laser writing combined with a super-fine inkjet process.It has a volume of less than 100×100×300μm^(3).Its tailored and chirped high-frequency grating enables strongly dispersive behaviour.The miniature spectrometer features a wavelength range of 200 nm in the visible range from 490 nm to 690 nm.It has a spectral resolution of 9.2±1.1 nm at 532 nm and 17.8±1.7 nm at a wavelength of 633 nm.Printing this spectrometer directly onto camera sensors is feasible and can be replicated for use as a macro-pixel of a snapshot hyperspectral camera.展开更多
Plasmonic hybrid nanomaterials are highly desirable in advanced sensing applications.Different components in these materials undertake distinct roles and work collectively.One material component may act as an efficien...Plasmonic hybrid nanomaterials are highly desirable in advanced sensing applications.Different components in these materials undertake distinct roles and work collectively.One material component may act as an efficient light concentrator and optical probe,whereas another provides specific chemical or biological functionality.In this work,we present DNA-assembled bimetallic plasmonic nanostructures and demonstrate their application for the all-optical detection of hydrogen.Gold(Au)nanorods are functionalized with DNA strands,which serve both as linkers and seeding sites for the growth of palladium(Pd)nanocrystals and facilitate reliable positioning of Pd satellites around an Au nanorod at an ultrashort spacing in the nanometer range.Dark-field scattering spectra of single Au–DNA–Pd nanorods were recorded during controlled cycles of hydrogen gas exposure,and an unambiguous concentration-dependent optical response was observed.Our method enables,for the first time,the all-optical detection of hydrogen-induced phase-change processes in sub-5-nm Pd nanocrystals at the single-antenna level.By substituting the Pd satellites with other functional materials,our sensor platform can be extended to plasmonic sensing of a multitude of chemical and biological reagents,both in liquid and gaseous phases.展开更多
NaYF_(4):Eu nanorods with high aspect ratios are elaborated and optically trapped using dual fiber optical tweezers in a counterpropagating geometry. High trapping efficiency is observed using converging beams, emitte...NaYF_(4):Eu nanorods with high aspect ratios are elaborated and optically trapped using dual fiber optical tweezers in a counterpropagating geometry. High trapping efficiency is observed using converging beams, emitted from diffractive Fresnel lenses directly 3D printed onto cleaved fiber facets. Stable nanorod trapping and alignment are reported for a fiber-to-fiber distance of 200 μm and light powers down to 10 m W. Trapping of nanorod clusters containing one to three nanorods and the coupling of nanorod motion in both axial and transverse directions are considered and discussed. The europium emission is studied by polarization-resolved spectroscopy with particular emphasis on the magnetic and electric dipole transitions. The respective σ and π orientations of the different emission lines are determined. The angles with respect to the nanorod axes of the corresponding magnetic and electric dipoles are calculated. Mono-exponential emission decay with decay time of 4–5 ms is reported. It is shown that the nanorod orientation can be determined by purely spectroscopic means.展开更多
Future quantum technology relies crucially on building quantum networks with high fidelity.To achieve this challenging goal,it is of utmost importance to connect individual quantum systems such that their emitted sing...Future quantum technology relies crucially on building quantum networks with high fidelity.To achieve this challenging goal,it is of utmost importance to connect individual quantum systems such that their emitted single photons overlap with the highest possible degree of coherence.This requires perfect mode overlap of the emitted light from different emitters,which necessitates the use of single-mode fibres.Here,we present an advanced manufacturing approach to accomplish this task.We combined 3D printed complex micro-optics,such as hemispherical and Weierstrass solid immersion lenses,as well as total internal reflection solid immersion lenses,on top of individual indium arsenide quantum dots with 3D printed optics on single-mode fibres and compared their key features.We observed a systematic increase in the collection efficiency under variations of the lens geometry from roughly 2 for hemispheric solid immersion lenses up to a maximum of greater than 9 for the total internal reflection geometry.Furthermore,the temperature-induced stress was estimated for these particular lens dimensions and results to be approximately 5 meV.Interestingly,the use of solid immersion lenses further increased the localisation accuracy of the emitters to less than 1 nm when acquiring micro-photoluminescence maps.Furthermore,we show that the single-photon character of the source is preserved after device fabrication,reaching a g^((2))(0)value of approximately 0.19 under pulsed optical excitation.The printed lens device can be further joined with an optical fibre and permanently fixed.This integrated system can be cooled by dipping into liquid helium using a Stirling cryocooler or by a closed-cycle helium cryostat without the necessity for optical windows,as all access is through the integrated single-mode fibre.We identify the ideal optical designs and present experiments that demonstrate excellent high-rate single-photon emission.展开更多
We introduce an extremely simple and highly stable system for stimulated Raman scattering(SRS)microscopy.An 8-W,450-fs Yb:KGW bulk oscillator with 41 MHz repetition rate pumps an optical parametric amplifier,which is ...We introduce an extremely simple and highly stable system for stimulated Raman scattering(SRS)microscopy.An 8-W,450-fs Yb:KGW bulk oscillator with 41 MHz repetition rate pumps an optical parametric amplifier,which is seeded by a cw tunable external cavity diode laser.The output radiation is frequency doubled in a long PPLN crystal and generates 1.5-ps long narrowband pump pulses that are tunable between 760 and 820 nm with 450 mW average power.Part of the oscillator output is sent through an etalon and creates Stokes pulses with 100 mW average power and 1.7 ps duration.We demonstrate SRS microscopy at a 30-μs pixel dwell time with high chemical contrast,signal-to-noise ratio in excess of 45 and no need for balanced detection,thanks to the favorable noise properties of the bulk solid-state system.Cw seeding intrinsically ensures low spectral drift.We discuss its application to chemical contrast microscopy of freshly prepared plant tissue sections at different vibrational bands.展开更多
Topology is the study of geometrical properties and spatial relations unaffected by continuous changes and has become an important tool for understanding complex physical systems.Although recent optical experiments ha...Topology is the study of geometrical properties and spatial relations unaffected by continuous changes and has become an important tool for understanding complex physical systems.Although recent optical experiments have inferred the existence of vector fields with the topologies of merons,the inability to extract the full three-dimensional vectors misses a richer set of topologies that have not yet been fully explored.We extend the study of the topology of electromagnetic fields on surfaces to a spin quasi-particle with the topology of a meron pair,formed by interfering surface plasmon polaritons(SPPs),and show that the in-plane vectors are constrained by the embedding topology of the space as dictated by the Poincaré–Hopf theorem.In addition,we explore the time evolution of the three-dimensional topology of the spin field formed by femtosecond laser pulses.These experiments are possible using our here-developed method called polarimetric photo-emission electron microscopy(polarimetric PEEM),which combines an optical pump–probe technique and polarimetry with PEEM.This method allows for the accurate generation of SPP fields and their subsequent measurement,revealing both the spatial distribution of the full three-dimensional electromagnetic fields at deep subwavelength resolution and their time evolution.展开更多
Levitated dielectric particles in a vacuum have emerged as a new platform in quantum science,with applications ranging from precision acceleration and force sensing to testing quantum physics beyond the microscopic do...Levitated dielectric particles in a vacuum have emerged as a new platform in quantum science,with applications ranging from precision acceleration and force sensing to testing quantum physics beyond the microscopic domain.Traditionally,particle levitation relies on optical tweezers formed by tightly focused laser beams,which typically require multiple bulk optical elements aligned in free space,limiting robustness and scalability of the system.To address these challenges,we employ a single optical fiber equipped with a high-numericalaperture(NA)lens directly printed onto the fiber facet.This enables a compact yet robust optical levitation and detection system composed entirely of fiber-based components,eliminating the need for complex alignment.The high NA of the printed lens allows stable single-beam trapping of a dielectric nanoparticle in a vacuum,even while the fiber is in controlled motion.The high NA also allows for collecting scattered light from the particle with excellent collection efficiency,thus enabling efficient detection and feedback stabilization of the particle's motion.Our platform paves the way for practical and portable sensors based on levitated particles and provides simple yet elegant solutions to complex experiments requiring the integration of levitated particles.展开更多
基金funded by the Villum Fonden(Award in Technical and Natural Sciences 2019 and Grant No.37372)Danmarks Frie Forskningsfond(Grant No.1134-00010B)+1 种基金support from the European Union’s Horizon 2020 Research and Innovation Program under the Marie Skłodowska-Curie Action(Grant Agreement No.713694)support from the China Scholarship Council(Grant No.202108330079).
文摘Electrically connected optical metasurfaces with high efficiencies are crucial for developing spatiotemporal metadevices with ultrahigh spatial and ultrafast temporal resolutions.While efficient metal–insulator–metal(MIM)metasurfaces containing discretized meta-atoms require additional electrodes,Babinet-inspired slot-antenna-based plasmonic metasurfaces suffer from low efficiencies and limited phase coverage for copolarized optical fields.Capitalizing on the concepts of conventional MIM and slot-antenna metasurfaces,we design and experimentally demonstrate a new type of optical reflective metasurfaces consisting of mirrorcoupled slot antennas(MCSAs).By tuning the dimensions of rectangular-shaped nanoapertures atop a dielectric-coated gold mirror,we achieve efficient phase modulation within a sufficiently large range of 320 deg and realize functional phase-gradient metadevices for beam steering and beam splitting in the near-infrared range.The fabricated samples show(22%2%)diffraction efficiency for beam steering and(17%1%)for beam splitting at the wavelength of 790 nm.The considered MCSA configuration,dispensing with auxiliary electrodes,offers an alternative and promising platform for electrically controlled reflective spatiotemporal metasurfaces.
基金supported by the National Health and Medical Research Council Development(Grant No.2022337)the Ideas Grant(Grant No.2001646),the Investigator Grant(Grant No.2008462)+9 种基金the Heart Foundation Future Leader Fellowship(Grant Nos.105608 and 106656)the Hospital Research Foundation Project(Grant No.2022-CP-IDMH-014-83100)Australia-Germany Joint Research Co-operation Scheme(UA-DAAD)Baden-Wuerttemberg-Stiftung(Opterial)European Research Council(Advanced Grant Complexplas,PoC Grant 3DPrintedOptics)Bundesministerium für Bildung und Forschung(3DPrintedOptics,Integrated3Dprint,QR.X,QR.N)Deutsche Forschungsgemeinschaft(German Research Foundation)(Grant No.431314977/GRK2642)HORIZON EUROPE European Innovation Council(Grant No.IV-Lab 101115545)Carl-Zeiss Foundation(EndoPrint3D,QPhoton)University of Stuttgart(Terra Incognita).
文摘A fundamental challenge in endoscopy is how to fabricate a small fiber-optic probe that can achieve comparable function to devices with large,complicated optics.To achieve high resolution over an extended depth of focus(DOF),the application of needle-like beams has been proposed.However,existing methods for miniaturized needle-beam designs fail to adequately correct astigmatism and other monochromatic aberrations,limiting the resolution of at least one axis.Here,we describe an approach to realize freeform beam-shaping endoscopic probes via two-photon polymerization three-dimensional(3D)printing.We present a design achieving<8μm lateral resolution with a DOF of∼800μm.The probe has a diameter of<260μm(without the torque coil and catheters)and is fabricated using a single printing step directly on the optical fiber.The probe was successfully utilized for intravascular imaging in living diabetic swine at multiple time points,as well as human atherosclerotic plaques ex vivo.To the best of our knowledge,this is the first report of a 3D-printed micro-optic for in vivo imaging of the coronary arteries.These results are a substantial step to enable the clinical adoption of both 3D-printed micro-optics and beam-tailoring devices.
基金support by the ERC Advanced Grant(COMPLEXPLAS)BMBF(13N9048 and 13N10146)+3 种基金the Baden Württemberg Stiftung(Internationale Spitzenforschung II)DFG(SPP1391,FOR730 and GI 269/11-1)SFB 917(Resistive Nanoswitches)support by the Carl-Zeiss-Stiftung。
文摘Compact nanophotonic elements exhibiting adaptable properties are essential components for the miniaturization of powerful optical technologies such as adaptive optics and spatial light modulators.While the larger counterparts typically rely on mechanical actuation,this can be undesirable in some cases on a microscopic scale due to inherent space restrictions.Here,we present a novel design concept for highly integrated active optical components that employs a combination of resonant plasmonic metasurfaces and the phase-change material Ge3Sb2Te6.In particular,we demonstrate beam switching and bifocal lensing,thus,paving the way for a plethora of active optical elements employing plasmonic metasurfaces,which follow the same design principles.
基金funded by the Australian Research Council(CE140100003)a Premier’s Research and Industry Fund grant provided by the South Australian Government Department for Industry and Skills+5 种基金BMBF PRINTOPTICS(13N14096,13N14097),Baden-Wurttemberg(BW)Stiftung OPTERIAL,European Research Council Advanced Grant COMPLEXPLAS,European Research Council Proof of Concept 3DPrintedOptics,and German Research Foundation(DFG)Integrated quantum science and technology(IQST)the National Health and Medical Research Council(NHMRC,Principle Research Fellowship 1111630)the National Heart Foundation(Lin Huddleston Senior Fellowship,and Postdoctoral Fellowship 102093)the University of Adelaide(Faculty of Health and Medical Sciences Emerging Leadership Program grant and Research Travel Award)Australia-Germany Joint Research Co-operation Scheme(UA-DAAD).
文摘Preclinical and clinical diagnostics increasingly rely on techniques to visualize internal organs at high resolution via endoscopes.Miniaturized endoscopic probes are necessary for imaging small luminal or delicate organs without causing trauma to tissue.However,current fabrication methods limit the imaging performance of highly miniaturized probes,restricting their widespread application.To overcome this limitation,we developed a novel ultrathin probe fabrication technique that utilizes 3D microprinting to reliably create side-facing freeform micro-optics(<130μm diameter)on single-mode fibers.Using this technique,we built a fully functional ultrathin aberration-corrected optical coherence tomography probe.This is the smallest freeform 3D imaging probe yet reported,with a diameter of 0.457 mm,including the catheter sheath.We demonstrated image quality and mechanical flexibility by imaging atherosclerotic human and mouse arteries.The ability to provide microstructural information with the smallest optical coherence tomography catheter opens a gateway for novel minimally invasive applications in disease.
基金This work was also supported by Baden-Wurttemberg-Stiftung(Opterial),European Research Council(ERC Advanced Grant Complexplas&ERC PoC Grant 3DPrintedOptics)Bundesministerium fur Bildung und Forschung,Deutsche Forschungsgemeinschaft,(SPP1839"Tailored Disorder"and GRK2642"Towards Graduate Experts in Photonic Quantum Technologies")by the Ministerium fur Wissenschaft,Forschung und Kunst Baden-Wurttemberg(RisC Project"Mie Voids",ZAQuant).
文摘Manipulating light on the nanoscale has become a central challenge in metadevices,resonant surfaces,nanoscale optical sensors,and many more,and it is largely based on resonant light confinement in dispersive and lossy metals and dielectrics.Here,we experimentally implement a novel strategy for dielectric nanophotonics:Resonant subwavelength localized confinement of light in air.We demonstrate that voids created in high-index dielectric host materials support localized resonant modes with exceptional optical properties.Due to the confinement in air,the modes do not suffer from the loss and dispersion of the dielectric host medium.We experimentally realize these resonant Mie voids by focused ion beam milling into bulk silicon wafers and experimentally demonstrate resonant light confinement down to the UV spectral range at 265 nm(4.68 eV).Furthermore,we utilize the bright,intense,and naturalistic colours for nanoscale colour printing.Mie voids will thus push the operation of functional high-index metasurfaces into the blue and UV spectral range.The combination of resonant dielectric Mie voids with dielectric nanoparticles will more than double the parameter space for the future design of metasurfaces and other micro-and nanoscale optical elements.In particular,this extension will enable novel antenna and structure designs which benefit from the full access to the modal field inside the void as well as the nearly free choice of the high-index material for novel sensing and active manipulation strategies.
基金We gratefully acknowledge the funding by DFG(SPP1391,FOR730,and GI 269/11-1),BMBF(FARADAY,FKZ 13N12443)MWK,Baden-Wurttemberg Stiftung and ERC(ComplexPlas)JYC and DD also acknowledge support from Carl-Zeiss-Stiftung.
文摘We experimentally demonstrate an ultra-thin plasmonic optical rotator in the visible regime that induces a polarization rotation that is continuously tunable and switchable by an external magnetic field.The rotator is a magneto-plasmonic hybrid structure consisting of a magneto-optical EuSe slab and a one-dimensional plasmonic gold grating.At low temperatures,EuSe possesses a large Verdet constant and exhibits Faraday rotation,which does not saturate over a regime of several Tesla.By combining these properties with plasmonic Faraday rotation enhancement,a large tuning range of the polarization rotation of up to 8.4° for a film thickness of 220 nm is achieved.Furthermore,through experiments and simulations,we demonstrate that the unique dispersion properties of the structure enable us to tailor the wavelengths of the tunable polarization rotation to arbitrary spectral positions within the transparency window of the magneto-optical slab.The demonstrated concept might lead to important,highly integrated,non-reciprocal,photonic devices for light modulation,optical isolation,and magnetic field optical sensing.The simple fabrication of EuSe nanostructures by physical vapor deposition opens the way for many potentially interesting magneto-plasmonic systems and three-dimensional magneto-optical metamaterials.
基金supported by the National Research Foundation,Prime Minister’s Office,Singapore under Competitive Research Program Award NRF-CRP22-2019-0006the grant(R-261-518-004-720)from Advanced Research and Technology Innovation Centre(ARTIC)+4 种基金the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)-Project-ID 278162697-SFB 1242ERC Advanced Grant Complex Plan,BMBF,DFG and BW-Stiftungthe Research Grants Council of Hong Kong(CRF Grant No.C6013-18G)the City University of Hong Kong(Project No.9610434)the support from A*STAR under its AME YIRG Grant(Award No.A2084c0172).
文摘Nanophotonic platforms such as metasurfaces,achieving arbitrary phase profiles within ultrathin thickness,emerge as miniaturized,ultracompact and kaleidoscopic optical vortex generators.However,it is often required to segment or interleave independent sub-array metasurfaces to multiplex optical vortices in a single nano-device,which in turn affects the device’s compactness and channel capacity.Here,inspired by phyllotaxis patterns in pine cones and sunflowers,we theoretically prove and experimentally report that multiple optical vortices can be produced in a single compact phyllotaxis nanosieve,both in free space and on a chip,where one meta-atom may contribute to many vortices simultaneously.The time-resolved dynamics of on-chip interference wavefronts between multiple plasmonic vortices was revealed by ultrafast time-resolved photoemission electron microscopy.Our nature-inspired optical vortex generator would facilitate various vortex-related optical applications,including structured wavefront shaping,free-space and plasmonic vortices,and high-capacity information metaphotonics.
基金the ERC Advanced Grant(COMPLEXPLAS)DFG(Nos.SPP1391,SPP 1839,FOR730,and GI 269/11-1)+4 种基金the Bundesministerium für Bildung und Forschung(Nos.13N9048,13N10146,and PRINTOPTICS),the Carl Zeiss Foundationthe Baden-Württemberg Stiftung(Spitzenforschung II)the University of Stuttgart(open access fund)the EPSRC(No.EP/P001114/1)the SRPe PRER and PECRE Award 2017/18.
文摘We present a fully automated laser system with low-intensity noise for coherent Raman scattering microscopy.The robust two-color system is pumped by a solid-state oscillator,which provides Stokes pulses fixed at 1043 nm.The tunable pump pulses of 750 to 950 nm are generated by a frequency-doubled fiberfeedback femtosecond optical parametric oscillator.The resulting pulse duration of 1.2 ps provides a viable compromise between optimal coherent Raman scattering signal and the necessary spectral resolution.Thus a spectral range of 1015 to 3695 cm−1 with spectral resolution of<13 cm−1 can be addressed.
基金funded by Bundesministerium für Bildung und Forschung(Printoptics,Printfunction)Baden-Württemberg Stiftung gGmbH(Opterial)+2 种基金Ministerium für Wissenschaft,Forschung und Kunst Baden-Württemberg(funding line"RiSC")Vector-Stiftung(funding line"MINT Innovationen")the European Research Council(ComplexPlas,3DPrintedOptics)。
文摘The miniaturisation of spectroscopic measurement devices opens novel information channels for size critical applications such as endoscopy or consumer electronics.Computational spectrometers in the micrometre size range have been demonstrated,however,these are calibration sensitive and based on complex reconstruction algorithms.Herein we present an angle-insensitive 3D-printed miniature spectrometer with a direct separated spatial-spectral response.The spectrometer was fabricated via two-photon direct laser writing combined with a super-fine inkjet process.It has a volume of less than 100×100×300μm^(3).Its tailored and chirped high-frequency grating enables strongly dispersive behaviour.The miniature spectrometer features a wavelength range of 200 nm in the visible range from 490 nm to 690 nm.It has a spectral resolution of 9.2±1.1 nm at 532 nm and 17.8±1.7 nm at a wavelength of 633 nm.Printing this spectrometer directly onto camera sensors is feasible and can be replicated for use as a macro-pixel of a snapshot hyperspectral camera.
基金We thank K Hahn for help with structure imaging.AT and HG were financially supported by the Deutsche Forschungsgemeinschaft(SPP1391,FOR730,GI 269/11-1)the Bundesministerium fur Bildung und Forschung(13N9048 and 13N10146)+1 种基金the ERC Advanced Grant COMPLEXPLAS,the Baden-Wurttemberg Stiftung(Spitzenforschung II)and the Ministerium fur Wissenschaft,Forschung und Kunst Baden-Wu¨rttemberg(Az:7533-7-11.6-8)NL was supported by the Sofia Kovalevskaja Award of the Alexander von Humboldt Foundation and Grassroots Proposal M10331 from the Max Planck Institute for Intelligent Systems.BD was supported by National Science Foundation China(21173059,21222311,91127021)and 100-Talent Program of the Chinese Academy of Sciences.
文摘Plasmonic hybrid nanomaterials are highly desirable in advanced sensing applications.Different components in these materials undertake distinct roles and work collectively.One material component may act as an efficient light concentrator and optical probe,whereas another provides specific chemical or biological functionality.In this work,we present DNA-assembled bimetallic plasmonic nanostructures and demonstrate their application for the all-optical detection of hydrogen.Gold(Au)nanorods are functionalized with DNA strands,which serve both as linkers and seeding sites for the growth of palladium(Pd)nanocrystals and facilitate reliable positioning of Pd satellites around an Au nanorod at an ultrashort spacing in the nanometer range.Dark-field scattering spectra of single Au–DNA–Pd nanorods were recorded during controlled cycles of hydrogen gas exposure,and an unambiguous concentration-dependent optical response was observed.Our method enables,for the first time,the all-optical detection of hydrogen-induced phase-change processes in sub-5-nm Pd nanocrystals at the single-antenna level.By substituting the Pd satellites with other functional materials,our sensor platform can be extended to plasmonic sensing of a multitude of chemical and biological reagents,both in liquid and gaseous phases.
基金Agence Nationale de la Recherche (ANR-16-CE24-0014-01)Okinawa Institute of Science and Technology Graduate University+2 种基金Baden-Württemberg Stiftung (Operial)Bundesministerium für Bildung und Forschung (Printoptics)European Research Council (POC3DPrinted Optics)。
文摘NaYF_(4):Eu nanorods with high aspect ratios are elaborated and optically trapped using dual fiber optical tweezers in a counterpropagating geometry. High trapping efficiency is observed using converging beams, emitted from diffractive Fresnel lenses directly 3D printed onto cleaved fiber facets. Stable nanorod trapping and alignment are reported for a fiber-to-fiber distance of 200 μm and light powers down to 10 m W. Trapping of nanorod clusters containing one to three nanorods and the coupling of nanorod motion in both axial and transverse directions are considered and discussed. The europium emission is studied by polarization-resolved spectroscopy with particular emphasis on the magnetic and electric dipole transitions. The respective σ and π orientations of the different emission lines are determined. The angles with respect to the nanorod axes of the corresponding magnetic and electric dipoles are calculated. Mono-exponential emission decay with decay time of 4–5 ms is reported. It is shown that the nanorod orientation can be determined by purely spectroscopic means.
基金We acknowledge the financial support of the German Federal Ministry of Science and Education[Bundesministerium fur Bildung und Forschung(BMBF)]via the projects Printoptics,Printfunction,and Q.link.X 16KIS0862support via the project EMPIR 17FUN06 SIQUST+1 种基金This project received funding from Baden-Württemberg-Stiftung via the Opterial projectThis project received funding from the EMPIR programme co-financed by the participating states and from the European Union’s Horizon 2020 research and innovation programme.Furthermore,funding was received from the European Research Council(ERC)via the projects AdG ComplexPlas and PoC 3D PrintedOptics.It was also funded by the Deutsche Forschungsgemeinschaft(DFG)via the projects SPP1839,SPP1929,GRK2642,as well as the Center for Integrated Quantum Science and Technology(IQST).
文摘Future quantum technology relies crucially on building quantum networks with high fidelity.To achieve this challenging goal,it is of utmost importance to connect individual quantum systems such that their emitted single photons overlap with the highest possible degree of coherence.This requires perfect mode overlap of the emitted light from different emitters,which necessitates the use of single-mode fibres.Here,we present an advanced manufacturing approach to accomplish this task.We combined 3D printed complex micro-optics,such as hemispherical and Weierstrass solid immersion lenses,as well as total internal reflection solid immersion lenses,on top of individual indium arsenide quantum dots with 3D printed optics on single-mode fibres and compared their key features.We observed a systematic increase in the collection efficiency under variations of the lens geometry from roughly 2 for hemispheric solid immersion lenses up to a maximum of greater than 9 for the total internal reflection geometry.Furthermore,the temperature-induced stress was estimated for these particular lens dimensions and results to be approximately 5 meV.Interestingly,the use of solid immersion lenses further increased the localisation accuracy of the emitters to less than 1 nm when acquiring micro-photoluminescence maps.Furthermore,we show that the single-photon character of the source is preserved after device fabrication,reaching a g^((2))(0)value of approximately 0.19 under pulsed optical excitation.The printed lens device can be further joined with an optical fibre and permanently fixed.This integrated system can be cooled by dipping into liquid helium using a Stirling cryocooler or by a closed-cycle helium cryostat without the necessity for optical windows,as all access is through the integrated single-mode fibre.We identify the ideal optical designs and present experiments that demonstrate excellent high-rate single-photon emission.
基金support by the Carl Zeiss foundation and the Projekthaus NanoBioMater at the University of StuttgartERC(ComplexPlas)+3 种基金EU-COST(MP1302)the EU Graphene Flagship(contract no.CNECT-ICT-604391)BW-Stiftung,Deutsche Forschungsgemeinschaft,BMBFFondazione Cariplo through the 2012-0904 project.
文摘We introduce an extremely simple and highly stable system for stimulated Raman scattering(SRS)microscopy.An 8-W,450-fs Yb:KGW bulk oscillator with 41 MHz repetition rate pumps an optical parametric amplifier,which is seeded by a cw tunable external cavity diode laser.The output radiation is frequency doubled in a long PPLN crystal and generates 1.5-ps long narrowband pump pulses that are tunable between 760 and 820 nm with 450 mW average power.Part of the oscillator output is sent through an etalon and creates Stokes pulses with 100 mW average power and 1.7 ps duration.We demonstrate SRS microscopy at a 30-μs pixel dwell time with high chemical contrast,signal-to-noise ratio in excess of 45 and no need for balanced detection,thanks to the favorable noise properties of the bulk solid-state system.Cw seeding intrinsically ensures low spectral drift.We discuss its application to chemical contrast microscopy of freshly prepared plant tissue sections at different vibrational bands.
基金support from the ERC(Complexplas,3DPrintedoptics),DFG(SPP1391“Ultrafast Nanooptics,”CRC 1242“Non-Equilibrium Dynamics of Condensed Matter in the Time Domain”Grant Nos.278162697-SFB 1242 and GRK2642“Photonic Quantum Engineers”),BMBF(Printoptics),BW Stiftung(Spitzenforschung,Opterial),Carl-Zeiss Stiftungsupport from the MPI vip Professorship Program and from the DFG(Grant No.GRK2642“Photonic Quantum Engineers”)for a Mercator Fellowship.
文摘Topology is the study of geometrical properties and spatial relations unaffected by continuous changes and has become an important tool for understanding complex physical systems.Although recent optical experiments have inferred the existence of vector fields with the topologies of merons,the inability to extract the full three-dimensional vectors misses a richer set of topologies that have not yet been fully explored.We extend the study of the topology of electromagnetic fields on surfaces to a spin quasi-particle with the topology of a meron pair,formed by interfering surface plasmon polaritons(SPPs),and show that the in-plane vectors are constrained by the embedding topology of the space as dictated by the Poincaré–Hopf theorem.In addition,we explore the time evolution of the three-dimensional topology of the spin field formed by femtosecond laser pulses.These experiments are possible using our here-developed method called polarimetric photo-emission electron microscopy(polarimetric PEEM),which combines an optical pump–probe technique and polarimetry with PEEM.This method allows for the accurate generation of SPP fields and their subsequent measurement,revealing both the spatial distribution of the full three-dimensional electromagnetic fields at deep subwavelength resolution and their time evolution.
基金Carl-Zeiss-Stiftung(Johannes-Kepler Grant through IQST,Endo Print3D,QPhoton Holo Q)Deutsche Forschungsgemeinschaft(523178467,431314977/GRK2642)Bundesministerium für Bildung und Forschung(QR.X,QR.N,Integrated 3D Print)。
文摘Levitated dielectric particles in a vacuum have emerged as a new platform in quantum science,with applications ranging from precision acceleration and force sensing to testing quantum physics beyond the microscopic domain.Traditionally,particle levitation relies on optical tweezers formed by tightly focused laser beams,which typically require multiple bulk optical elements aligned in free space,limiting robustness and scalability of the system.To address these challenges,we employ a single optical fiber equipped with a high-numericalaperture(NA)lens directly printed onto the fiber facet.This enables a compact yet robust optical levitation and detection system composed entirely of fiber-based components,eliminating the need for complex alignment.The high NA of the printed lens allows stable single-beam trapping of a dielectric nanoparticle in a vacuum,even while the fiber is in controlled motion.The high NA also allows for collecting scattered light from the particle with excellent collection efficiency,thus enabling efficient detection and feedback stabilization of the particle's motion.Our platform paves the way for practical and portable sensors based on levitated particles and provides simple yet elegant solutions to complex experiments requiring the integration of levitated particles.
