Integrated optical chips have already been established for application in optical communication.They also offer interesting future perspectives for integrated quantum optics on a chip.At present,however,they are mostl...Integrated optical chips have already been established for application in optical communication.They also offer interesting future perspectives for integrated quantum optics on a chip.At present,however,they are mostly fabricated using essentially planar fabrication approaches like electron-beam lithography or UV optical lithography.Many further design options would arise if one had complete fabrication freedom in regard to the third dimension normal to the chip without having to give up the virtues and the know-how of existing planar fabrication technologies.As a step in this direction,we here use three-dimensional dip-in direct-laser-writing optical lithography to fabricate three-dimensional polymeric functional devices on pre-fabricated planar optical chips containing Si3N4 waveguides as well as grating couplers made by standard electron-beam lithography.The first example is a polymeric dielectric rectangular-shaped waveguide which is connected to Si3N4 waveguides and that is adiabatically twisted along its axis to achieve geometrical rotation of linear polarization on the chip.The rotator’s broadband performance at around 1550 nm wavelength is verified by polarization-dependent grating couplers.Such polarization rotation on the optical chip cannot easily be achieved by other means.The second example is a whispering-gallery-mode optical resonator connected to Si_(3)N_(4) waveguides on the chip via polymeric waveguides.By mechanically connecting the latter to the disk,we can control the coupling to the resonator and,at the same time,guarantee mechanical stability of the three-dimensional architecture on the chip.展开更多
Three-dimensional(3D)laser micro-and nanoprinting based upon multi-photon absorption has made its way from early scientific discovery to industrial manufacturing processes,e.g.,for advanced microoptical components.How...Three-dimensional(3D)laser micro-and nanoprinting based upon multi-photon absorption has made its way from early scientific discovery to industrial manufacturing processes,e.g.,for advanced microoptical components.However,so far,most realized 3D architectures are composed of only a single polymeric material.Here,we review 3D printing of multi-materials on the nano-and microscale.We start with material properties that have been realized,using multi-photon photoresists.Printed materials include bulk polymers,conductive polymers,metals,nanoporous polymers,silica glass,chalcogenide glasses,inorganic single crystals,natural polymers,stimuliresponsive materials,and polymer composites.Next,we review manual and automated processes achieving dissimilar material properties in a single 3D structure by sequentially photo-exposing multiple photoresists as 3D analogs of 2D multicolor printing.Instructive examples from biology,optics,mechanics,and electronics are discussed.An emerging approach–without counterpart in 2D graphical printing–prints 3D structures combining dissimilar material properties in one 3D structure by using only a single photoresist.A controlled stimulus applied during the 3D printing process defines and determines material properties on the voxel level.Change of laser power and/or wavelength,or application of quasi-static electric fields allow for the seamless manipulation of desired materials properties.展开更多
In recent years,multi-photon 3D laser printing has become a widely used tool for the fabrication of micro-and nanostructures for a large variety of applications.Typically,thorough sample characterisation is key for an...In recent years,multi-photon 3D laser printing has become a widely used tool for the fabrication of micro-and nanostructures for a large variety of applications.Typically,thorough sample characterisation is key for an efficient optimisation of the printing process.To date,three-dimensional microscopic inspection has usually been carried out on finished 3D printed microstructures,that is,using ex-situ approaches.In contrast,in-situ 3D characterization tools are desirable for quickly assessing the quality and properties of 3D printed microstructures.Along these lines,we present and characterise a Fourier-domain optical coherence tomography(FD-OCT)system that can be readily integrated into an existing 3D laser lithography setup.We demonstrate its capabilities by examining different 3D printed polymer microstructures immersed in a liquid photoresist.In such samples,local reflectivity arises from the(refractive-index)contrasts between the polymerised and non-polymerised regions.Thus,the refractive index of the printed material can be extracted.Furthermore,we demonstrate that the reflectivity of polymer-monomer transitions exhibits time-dependent behaviour after printing.Supported by transfer-matrix calculations,we explain this effect in terms of the time-dependent graded-index transition originating from monomer diffusion into the polymer matrix.Finally,we show exemplary 3D reconstructions of printed structures that can be readily compared with 3D computer designs.展开更多
One of the challenges in the field of multi-photon 3D laser printing lies in further increasing the print speed in terms of voxels/s.Here,we present a setup based on a 7×7 focus array(rather than 3×3 in our ...One of the challenges in the field of multi-photon 3D laser printing lies in further increasing the print speed in terms of voxels/s.Here,we present a setup based on a 7×7 focus array(rather than 3×3 in our previous work)and using a focus velocity of about 1 m/s(rather than 0.5 m/s in our previous work)at the diffraction limit(40×/NA1.4 microscope objective lens).Combined,this advance leads to a ten times increased print speed of about 108 voxels/s.We demonstrate polymer printing of a chiral metamaterial containing more than 1.7×10^(12) voxels as well as millions of printed microparticles for potential pharmaceutical applications.The critical high-quality micro-optical components of the setup,namely a diffractive optical element generating the 7×7 beamlets and a 7×7 lens array,are manufactured by using a commercial two-photon grayscale 3D laser printer.展开更多
State-of-the-art commercially available 3D laser micro-and nanoprinters using polymeric photoresists based on two-or multi-photon absorption rely on high-power pico-or femtosecond lasers,leading to fairly large and ex...State-of-the-art commercially available 3D laser micro-and nanoprinters using polymeric photoresists based on two-or multi-photon absorption rely on high-power pico-or femtosecond lasers,leading to fairly large and expensive instruments.Lately,we have introduced photoresists based on two-step absorption instead of two-photon absorption,allowing for the use of small and inexpensive continuous-wave 405 nm wavelength GaN semiconductor laser diodes with light-output powers below 1 mW.Here,using the identical photoresist system and similar laser diodes,we report on the design,construction,and characterization of a 3D laser nanoprinter that fits into a shoe box.This shoe box contains all optical components,namely the mounted laser,the collimation-and beam-shaping optics,a miniature MEMS xy-scanner,a tube lens,the focusing microscope objective lens(NA=1.4,100×magnification),a piezo slip-stick z-stage,the sample holder,a camera monitoring system,LED sample illumination,as well as the miniaturized control electronics employing a microcontroller.We present a gallery of example 3D structures printed with this instrument.We achieve about 100 nm lateral spatial resolution and focus scan speeds of about 1 mm/s.Potentially,our shoe-box-sized system can be made orders of magnitude less expensive than today’s commercial systems.展开更多
Transformation optics allows for mapping the geometry of space onto spatially inhomogeneous optical properties of metamaterials. Invisibility cloaks are a demanding benchmark example because they were believed impossi...Transformation optics allows for mapping the geometry of space onto spatially inhomogeneous optical properties of metamaterials. Invisibility cloaks are a demanding benchmark example because they were believed impossible just a few years ago. For the fabrication of visible-frequency, broadband, polarization-independent, three-dimensional invisibility cloaks for the amplitude and phase of light, we use direct-laser-writing （DLW） optical lithography combined with stimulated-emission depletion （STED）, which breaks Abbe＇s diffraction limit. The transformation idea can also be translated to other areas such as mechanics （precisely, elastodynamics） and thermodynamics. Corresponding experiments will be discussed, too展开更多
基金support by the China Scholarship Council(CSC).This research has additionally been funded by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany’s Excellence Strategy via the Excellence Cluster“3D Matter Made to Order”(Grant No.EXC-2082/1-390761711)which has also been supported by the Carl Zeiss Foundation through the“Carl-Zeiss-Foundation-Focus@HEiKA”,by the State of Baden-Württemberg,and by the Karlsruhe Institute of Technology(KIT).We further acknowledge support by the Helmholtz program“Materials Systems Engineering”(MSE).Muamer Kadic is grateful for support by the EIPHI Graduate School(Grant No.ANR-17-EURE-0002)Changguo Wang is grateful for support by the National Natural Science Foundation of China(Grant No.12172102).
基金We acknowledges support by DFG grant PE 1832/1-1 and PE 1832/2-1the Helmholtz Society through grant HIRG-0005.
文摘Integrated optical chips have already been established for application in optical communication.They also offer interesting future perspectives for integrated quantum optics on a chip.At present,however,they are mostly fabricated using essentially planar fabrication approaches like electron-beam lithography or UV optical lithography.Many further design options would arise if one had complete fabrication freedom in regard to the third dimension normal to the chip without having to give up the virtues and the know-how of existing planar fabrication technologies.As a step in this direction,we here use three-dimensional dip-in direct-laser-writing optical lithography to fabricate three-dimensional polymeric functional devices on pre-fabricated planar optical chips containing Si3N4 waveguides as well as grating couplers made by standard electron-beam lithography.The first example is a polymeric dielectric rectangular-shaped waveguide which is connected to Si3N4 waveguides and that is adiabatically twisted along its axis to achieve geometrical rotation of linear polarization on the chip.The rotator’s broadband performance at around 1550 nm wavelength is verified by polarization-dependent grating couplers.Such polarization rotation on the optical chip cannot easily be achieved by other means.The second example is a whispering-gallery-mode optical resonator connected to Si_(3)N_(4) waveguides on the chip via polymeric waveguides.By mechanically connecting the latter to the disk,we can control the coupling to the resonator and,at the same time,guarantee mechanical stability of the three-dimensional architecture on the chip.
基金funding by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany’s Excellence Strategy for the Excellence Cluster“3D Matter Made to Order”(EXC 2082/1–390761711)by the Carl Zeiss Foundation,by the Helmholtz program“Materials Systems Engineering(MSE)”by the Karlsruhe School of Optics and Photonics(KSOP).
文摘Three-dimensional(3D)laser micro-and nanoprinting based upon multi-photon absorption has made its way from early scientific discovery to industrial manufacturing processes,e.g.,for advanced microoptical components.However,so far,most realized 3D architectures are composed of only a single polymeric material.Here,we review 3D printing of multi-materials on the nano-and microscale.We start with material properties that have been realized,using multi-photon photoresists.Printed materials include bulk polymers,conductive polymers,metals,nanoporous polymers,silica glass,chalcogenide glasses,inorganic single crystals,natural polymers,stimuliresponsive materials,and polymer composites.Next,we review manual and automated processes achieving dissimilar material properties in a single 3D structure by sequentially photo-exposing multiple photoresists as 3D analogs of 2D multicolor printing.Instructive examples from biology,optics,mechanics,and electronics are discussed.An emerging approach–without counterpart in 2D graphical printing–prints 3D structures combining dissimilar material properties in one 3D structure by using only a single photoresist.A controlled stimulus applied during the 3D printing process defines and determines material properties on the voxel level.Change of laser power and/or wavelength,or application of quasi-static electric fields allow for the seamless manipulation of desired materials properties.
基金This work was funded by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany’s Excellence Strategy 2082/1-390761711(Excellence Cluster“3D Matter Made to Order”).
文摘In recent years,multi-photon 3D laser printing has become a widely used tool for the fabrication of micro-and nanostructures for a large variety of applications.Typically,thorough sample characterisation is key for an efficient optimisation of the printing process.To date,three-dimensional microscopic inspection has usually been carried out on finished 3D printed microstructures,that is,using ex-situ approaches.In contrast,in-situ 3D characterization tools are desirable for quickly assessing the quality and properties of 3D printed microstructures.Along these lines,we present and characterise a Fourier-domain optical coherence tomography(FD-OCT)system that can be readily integrated into an existing 3D laser lithography setup.We demonstrate its capabilities by examining different 3D printed polymer microstructures immersed in a liquid photoresist.In such samples,local reflectivity arises from the(refractive-index)contrasts between the polymerised and non-polymerised regions.Thus,the refractive index of the printed material can be extracted.Furthermore,we demonstrate that the reflectivity of polymer-monomer transitions exhibits time-dependent behaviour after printing.Supported by transfer-matrix calculations,we explain this effect in terms of the time-dependent graded-index transition originating from monomer diffusion into the polymer matrix.Finally,we show exemplary 3D reconstructions of printed structures that can be readily compared with 3D computer designs.
基金funding by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany’s Excellence Strategy for the Excellence Cluster“3D Matter Made to Order”(2082/1-390761711)by the Carl Zeiss Foundation,and by the Helmholtz program Materials Systems Engineering.
文摘One of the challenges in the field of multi-photon 3D laser printing lies in further increasing the print speed in terms of voxels/s.Here,we present a setup based on a 7×7 focus array(rather than 3×3 in our previous work)and using a focus velocity of about 1 m/s(rather than 0.5 m/s in our previous work)at the diffraction limit(40×/NA1.4 microscope objective lens).Combined,this advance leads to a ten times increased print speed of about 108 voxels/s.We demonstrate polymer printing of a chiral metamaterial containing more than 1.7×10^(12) voxels as well as millions of printed microparticles for potential pharmaceutical applications.The critical high-quality micro-optical components of the setup,namely a diffractive optical element generating the 7×7 beamlets and a 7×7 lens array,are manufactured by using a commercial two-photon grayscale 3D laser printer.
基金We thank Vincent Hahn,Michael Thiel(Nanoscribe),and Matthias Blaicher(Nanoscribe)for discussions.We acknowledge funding by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under Germany’s Excellence Strategy for the Excellence Cluster“3D Matter Made to Order”(2082/1-390761711)by the Carl Zeiss Foundation,by the Helmholtz program“Science and Technology of Nanosystems”,by the Karlsruhe School of Optics and Photonics(KSOP),by the Max Planck School of Photonics(MPSP)by Nanoscribe-A BICO company.
文摘State-of-the-art commercially available 3D laser micro-and nanoprinters using polymeric photoresists based on two-or multi-photon absorption rely on high-power pico-or femtosecond lasers,leading to fairly large and expensive instruments.Lately,we have introduced photoresists based on two-step absorption instead of two-photon absorption,allowing for the use of small and inexpensive continuous-wave 405 nm wavelength GaN semiconductor laser diodes with light-output powers below 1 mW.Here,using the identical photoresist system and similar laser diodes,we report on the design,construction,and characterization of a 3D laser nanoprinter that fits into a shoe box.This shoe box contains all optical components,namely the mounted laser,the collimation-and beam-shaping optics,a miniature MEMS xy-scanner,a tube lens,the focusing microscope objective lens(NA=1.4,100×magnification),a piezo slip-stick z-stage,the sample holder,a camera monitoring system,LED sample illumination,as well as the miniaturized control electronics employing a microcontroller.We present a gallery of example 3D structures printed with this instrument.We achieve about 100 nm lateral spatial resolution and focus scan speeds of about 1 mm/s.Potentially,our shoe-box-sized system can be made orders of magnitude less expensive than today’s commercial systems.
文摘Transformation optics allows for mapping the geometry of space onto spatially inhomogeneous optical properties of metamaterials. Invisibility cloaks are a demanding benchmark example because they were believed impossible just a few years ago. For the fabrication of visible-frequency, broadband, polarization-independent, three-dimensional invisibility cloaks for the amplitude and phase of light, we use direct-laser-writing （DLW） optical lithography combined with stimulated-emission depletion （STED）, which breaks Abbe＇s diffraction limit. The transformation idea can also be translated to other areas such as mechanics （precisely, elastodynamics） and thermodynamics. Corresponding experiments will be discussed, too
