The generation of tunably focused light at remote locations is a critical photonic functionality for a wide range of applications.Here,we present a novel concept in the emerging field of Metafibers that achieves,for t...The generation of tunably focused light at remote locations is a critical photonic functionality for a wide range of applications.Here,we present a novel concept in the emerging field of Metafibers that achieves,for the first time,fast,alignment-free,fiber-integrated spatial focus control in a monolithic arrangement.This is enabled by 3D nanoprinted intensity-sensitive phase-only on-fiber holograms,which establish a direct correlation between the intensity distribution in the hologram plane and the focus position.Precise adjustment to the relative power between the modes of a dual-core fiber generates a power-controlled interference pattern within the hologram,enabling controlled and dynamic focus shifts.This study addresses all relevant aspects,including computational optimization,advanced 3D nanoprinting,and tailored fiber fabrication.Experimental results supported by simulations validate the feasibility and efficiency of this monolithic Metafiber platform,which enables fast focus modulation and has transformative potential in optical manipulation,high-speed laser micromachining,telecommunications,and minimally invasive surgery.展开更多
The integration of functional components into flexible photonic environments is a critical area of research in integrated photonics and is essential for high-precision sensing.This work presents a novel concept of int...The integration of functional components into flexible photonic environments is a critical area of research in integrated photonics and is essential for high-precision sensing.This work presents a novel concept of interfacing square-core hollow-core waveguides with commercially available optical fibers using 3D nanoprinting,and demonstrates its practical relevance through a nanoscience-based characterization technique.In detail,this innovative concept results in a monolithic,fully fiber-integrated device with key advantages such as alignment-free operation,high-purity fundamental mode excitation,full polarization control,and a unique handling flexibility.For the first time,the application potential of a fiber-interfaced waveguide in nanoscale analysis is demonstrated by performing nanoparticle-tracking-analysis experiments.These experiments involve the tracking and analysis of individual gold nanospheres diffusing in the hollow core waveguide,enabled by nearly aberration-free imaging,extended observation times,and homogeneous light-line illumination.The study comprehensively covers design strategy,experimental implementation,key principles,optical characterization,and practical applications.The fiber-interfaced hollow-core waveguide concept offers significant potential for applications in bioanalytics,environmental sciences,quantum technologies,optical manipulation,and life sciences.It also paves the way for the development of novel all-fiber devices that exploit enhanced light-matter interaction in a monolithic form suitable for flexible and remote applications.展开更多
Twisted optical fibers are a promising platform for manipulating circularly polarized light and orbital angular momentum beams for applications such as nonlinear frequency conversion,optical communication,or chiral se...Twisted optical fibers are a promising platform for manipulating circularly polarized light and orbital angular momentum beams for applications such as nonlinear frequency conversion,optical communication,or chiral sensing.However,integration into chip-scale technology is challenging because twisted fibers are incompatible with planar photonics and the achieved twist rates are limited.Here,we address these challenges by introducing the concept of 3D-nanoprinted on-chip twisted hollow-core light cages.We show theoretically and experimentally that the geometrical twisting of light cages forces the fundamental core mode of a given handedness to couple with selected higher-order core modes,resulting in strong circular dichroism(CD).These chiral resonances result from the angular momentum harmonics of the fundamental mode,allowing us to predict their spectral locations and the occurrence of circular birefringence.Twisted light cages enable very high twist rates and CD,exceeding those of twisted hollow-core fibers by more than two orders of magnitude(twist period,90μm;CD,0.8 dB∕mm).Moreover,the unique cage design provides lateral access to the central core region,enabling future applications in chiral spectroscopy.Therefore,the presented concept opens a path for translating twisted fiber research to on-chip technology,resulting in a new platform for integrated chiral photonics.展开更多
Strong focusing on diffraction-limited spots is essential for many photonic applications and is particularly relevant for optical trapping;however,all currently used approaches fail to simultaneously provide flexible ...Strong focusing on diffraction-limited spots is essential for many photonic applications and is particularly relevant for optical trapping;however,all currently used approaches fail to simultaneously provide flexible transportation of light,straightforward implementation,compatibility with waveguide circuitry,and strong focusing.Here,we demonstrate the design and 3D nanoprinting of an ultrahigh numerical aperture meta-fibre for highly flexible optical trapping.Taking into account the peculiarities of the fibre environment,we implemented an ultrathin meta-lens on the facet of a modified single-mode optical fibre via direct laser writing,leading to a diffraction-limited focal spot with a recordhigh numerical aperture of up to NA≈0.9.The unique capabilities of this flexible,cost-effective,bio-and fibre-circuitrycompatible meta-fibre device were demonstrated by optically trapping microbeads and bacteria for the first time with only one single-mode fibre in combination with diffractive optics.Our study highlights the relevance of the unexplored but exciting field of meta-fibre optics to a multitude of fields,such as bioanalytics,quantum technology and life sciences.展开更多
Controlling coherent interaction between optical fields and quantum systems in scalable,integrated platforms is essential for quantum technologies.Miniaturised,warm alkali-vapour cells integrated with on-chip photonic...Controlling coherent interaction between optical fields and quantum systems in scalable,integrated platforms is essential for quantum technologies.Miniaturised,warm alkali-vapour cells integrated with on-chip photonic devices represent an attractive system,in particular for delay or storage of a single-photon quantum state.Hollow-core fibres or planar waveguides are widely used to confine light over long distances enhancing light-matter interaction in atomic-vapour cells.However,they suffer from inefficient filling times,enhanced dephasing for atoms near the surfaces,and limited light-matter overlap.We report here on the observation of modified electromagnetically induced transparency for a non-diffractive beam of light in an on-chip,laterally-accessible hollow-core light cage.Atomic layer deposition of an alumina nanofilm onto the light-cage structure was utilised to precisely tune the high-transmission spectral region of the light-cage mode to the operation wavelength of the atomic transition,while additionally protecting the polymer against the corrosive alkali vapour.The experiments show strong,coherent light-matter coupling over lengths substantially exceeding the Rayleigh range.Additionally,the stable non-degrading performance and extreme versatility of the light cage provide an excellent basis for a manifold of quantum-storage and quantumnonlinear applications,highlighting it as a compelling candidate for all-on-chip,integrable,low-cost,vapour-based photon delay.展开更多
We evaluate the sensing properties of plasmonic waveguide sensors by calculating their resonant transmission spectra in different regions of the non-Hermitian eigenmode space.We elucidate the pitfalls of using modal d...We evaluate the sensing properties of plasmonic waveguide sensors by calculating their resonant transmission spectra in different regions of the non-Hermitian eigenmode space.We elucidate the pitfalls of using modal dispersion calculations in isolation to predict plasmonic sensor performance,which we address by using a simple model accounting for eigenmode excitation and propagation.Our transmission calculations show that resonant wavelength and spectral width crucially depend on the length of the sensing region,so that no single criterion obtained from modal dispersion calculations alone can be used as a proxy for sensitivity.Furthermore,we find that the optimal detection limits occur where directional coupling is supported,where the narrowest spectra occur.Such narrow spectral features can only be measured by filtering out all higher-order modes at the output,e.g.,via a single-mode waveguide.Our calculations also confirm a characteristic square root dependence of the eigenmode splitting with respect to the permittivity perturbation at the exceptional point,which we show can be identified through the sensor beat length at resonance.This work provides a convenient framework for designing and characterizing plasmonic waveguide sensors when comparing them with experimental measurements.展开更多
Nonlinear frequency conversion is a pathway to unlock undiscovered physics and implement tailored light sources for spectroscopy or medicine.A key challenge is the establishment of spectrally flat outputs,which is par...Nonlinear frequency conversion is a pathway to unlock undiscovered physics and implement tailored light sources for spectroscopy or medicine.A key challenge is the establishment of spectrally flat outputs,which is particularly demanding in the context of soliton-based light conversion at low pump energy.Here,we introduce the concept of controlling nonlinear frequency conversion by longitudinally varying resonances,allowing the shaping of soliton dynamics and achieving broadband spectra with substantial spectral flatness.Longitudinally varying resonances are realised by nanofilms with gradually changing thicknesses located on the core of an advanced microstructured fibre.Nanofilms with engineered thickness profiles are fabricated by tilted deposition,representing a waveguidecompatible approach to nano-fabrication,and inducing well-controlled resonances into the system,allowing unique dispersion control along the fibre length.Key features and dependencies are examined experimentally,showing improved bandwidth and spectral flatness via multiple dispersive wave generation and dispersionassisted soliton Raman shifts while maintaining excellent pulse-to-pulse stability and coherence in simulations,suggesting the relevance of our findings for basic science as well as tailored light sources.展开更多
基金German Research Foundation(DFG)via the grants SCHM2655/21-1,SCHM2655/23-1,QI 140/2-1。
文摘The generation of tunably focused light at remote locations is a critical photonic functionality for a wide range of applications.Here,we present a novel concept in the emerging field of Metafibers that achieves,for the first time,fast,alignment-free,fiber-integrated spatial focus control in a monolithic arrangement.This is enabled by 3D nanoprinted intensity-sensitive phase-only on-fiber holograms,which establish a direct correlation between the intensity distribution in the hologram plane and the focus position.Precise adjustment to the relative power between the modes of a dual-core fiber generates a power-controlled interference pattern within the hologram,enabling controlled and dynamic focus shifts.This study addresses all relevant aspects,including computational optimization,advanced 3D nanoprinting,and tailored fiber fabrication.Experimental results supported by simulations validate the feasibility and efficiency of this monolithic Metafiber platform,which enables fast focus modulation and has transformative potential in optical manipulation,high-speed laser micromachining,telecommunications,and minimally invasive surgery.
基金supported by the German Research Foundation via the grants SCHM2655/15-1 and SCHM2655/22-1supported by Fundacao para a Ciencia e a Tecnologia(FCT/MCTES)by national funds(OE)UIDB/50025/2020,UIDP/50025/2020&CEECINST/00013/2021/CP2779/CT0014through the PhD research grant 2022.09911.BD.
文摘The integration of functional components into flexible photonic environments is a critical area of research in integrated photonics and is essential for high-precision sensing.This work presents a novel concept of interfacing square-core hollow-core waveguides with commercially available optical fibers using 3D nanoprinting,and demonstrates its practical relevance through a nanoscience-based characterization technique.In detail,this innovative concept results in a monolithic,fully fiber-integrated device with key advantages such as alignment-free operation,high-purity fundamental mode excitation,full polarization control,and a unique handling flexibility.For the first time,the application potential of a fiber-interfaced waveguide in nanoscale analysis is demonstrated by performing nanoparticle-tracking-analysis experiments.These experiments involve the tracking and analysis of individual gold nanospheres diffusing in the hollow core waveguide,enabled by nearly aberration-free imaging,extended observation times,and homogeneous light-line illumination.The study comprehensively covers design strategy,experimental implementation,key principles,optical characterization,and practical applications.The fiber-interfaced hollow-core waveguide concept offers significant potential for applications in bioanalytics,environmental sciences,quantum technologies,optical manipulation,and life sciences.It also paves the way for the development of novel all-fiber devices that exploit enhanced light-matter interaction in a monolithic form suitable for flexible and remote applications.
基金financial support from the German Research Foundation via Grant Nos.MA 4699/2-1,MA 4699/9-1,SCHM2655/11-1,SCHM2655/15-1,SCHM2655/8-1,SCHM2655/22-1,and WE 5815/5-1 and via project number 512648189。
文摘Twisted optical fibers are a promising platform for manipulating circularly polarized light and orbital angular momentum beams for applications such as nonlinear frequency conversion,optical communication,or chiral sensing.However,integration into chip-scale technology is challenging because twisted fibers are incompatible with planar photonics and the achieved twist rates are limited.Here,we address these challenges by introducing the concept of 3D-nanoprinted on-chip twisted hollow-core light cages.We show theoretically and experimentally that the geometrical twisting of light cages forces the fundamental core mode of a given handedness to couple with selected higher-order core modes,resulting in strong circular dichroism(CD).These chiral resonances result from the angular momentum harmonics of the fundamental mode,allowing us to predict their spectral locations and the occurrence of circular birefringence.Twisted light cages enable very high twist rates and CD,exceeding those of twisted hollow-core fibers by more than two orders of magnitude(twist period,90μm;CD,0.8 dB∕mm).Moreover,the unique cage design provides lateral access to the central core region,enabling future applications in chiral spectroscopy.Therefore,the presented concept opens a path for translating twisted fiber research to on-chip technology,resulting in a new platform for integrated chiral photonics.
文摘Strong focusing on diffraction-limited spots is essential for many photonic applications and is particularly relevant for optical trapping;however,all currently used approaches fail to simultaneously provide flexible transportation of light,straightforward implementation,compatibility with waveguide circuitry,and strong focusing.Here,we demonstrate the design and 3D nanoprinting of an ultrahigh numerical aperture meta-fibre for highly flexible optical trapping.Taking into account the peculiarities of the fibre environment,we implemented an ultrathin meta-lens on the facet of a modified single-mode optical fibre via direct laser writing,leading to a diffraction-limited focal spot with a recordhigh numerical aperture of up to NA≈0.9.The unique capabilities of this flexible,cost-effective,bio-and fibre-circuitrycompatible meta-fibre device were demonstrated by optically trapping microbeads and bacteria for the first time with only one single-mode fibre in combination with diffractive optics.Our study highlights the relevance of the unexplored but exciting field of meta-fibre optics to a multitude of fields,such as bioanalytics,quantum technology and life sciences.
基金supported by the German Research Foundation(DFG)Collaborative Research Center(CRC)SFB 787 project C2,the German Federal Ministry of Education and Research(BMBF)project Qthe DFG Collaborative Research Center(CRC)SFB 951 project B18+5 种基金the DFG projects SCHM2655/8-1,SCHM2655/11-1,SCHM2655/15-1,and MA 4699/2-1support by IRIS Adlershofthe European Commission for the Marie-Sklodowska-Curie action 797044the Lee-Lucas Chair in Experimental Physics at Imperial College Londonsupport by the Open Access Publication Fund of Humboldt-Universität zu BerlinOpen Access funding enabled and organized by Projekt DEAL.
文摘Controlling coherent interaction between optical fields and quantum systems in scalable,integrated platforms is essential for quantum technologies.Miniaturised,warm alkali-vapour cells integrated with on-chip photonic devices represent an attractive system,in particular for delay or storage of a single-photon quantum state.Hollow-core fibres or planar waveguides are widely used to confine light over long distances enhancing light-matter interaction in atomic-vapour cells.However,they suffer from inefficient filling times,enhanced dephasing for atoms near the surfaces,and limited light-matter overlap.We report here on the observation of modified electromagnetically induced transparency for a non-diffractive beam of light in an on-chip,laterally-accessible hollow-core light cage.Atomic layer deposition of an alumina nanofilm onto the light-cage structure was utilised to precisely tune the high-transmission spectral region of the light-cage mode to the operation wavelength of the atomic transition,while additionally protecting the polymer against the corrosive alkali vapour.The experiments show strong,coherent light-matter coupling over lengths substantially exceeding the Rayleigh range.Additionally,the stable non-degrading performance and extreme versatility of the light cage provide an excellent basis for a manifold of quantum-storage and quantumnonlinear applications,highlighting it as a compelling candidate for all-on-chip,integrable,low-cost,vapour-based photon delay.
文摘We evaluate the sensing properties of plasmonic waveguide sensors by calculating their resonant transmission spectra in different regions of the non-Hermitian eigenmode space.We elucidate the pitfalls of using modal dispersion calculations in isolation to predict plasmonic sensor performance,which we address by using a simple model accounting for eigenmode excitation and propagation.Our transmission calculations show that resonant wavelength and spectral width crucially depend on the length of the sensing region,so that no single criterion obtained from modal dispersion calculations alone can be used as a proxy for sensitivity.Furthermore,we find that the optimal detection limits occur where directional coupling is supported,where the narrowest spectra occur.Such narrow spectral features can only be measured by filtering out all higher-order modes at the output,e.g.,via a single-mode waveguide.Our calculations also confirm a characteristic square root dependence of the eigenmode splitting with respect to the permittivity perturbation at the exceptional point,which we show can be identified through the sensor beat length at resonance.This work provides a convenient framework for designing and characterizing plasmonic waveguide sensors when comparing them with experimental measurements.
基金support of the German Science Foundation via the Projects SCHM2655/9-1,SCHM2655/11-1,and SCHM2655/12-1This work was performed in part at the Optofab node of the Australian National Fabrication Facility(ANFF)utilising Commonwealth and South Australian State Government Funding.T.L.acknowledges support from the German Science Foundation DFG,IRTG 2101.H.E.and E.S.acknowledge support from the ARC Centre of Excellence for Nanoscale Biophotonics(CE140100003).
文摘Nonlinear frequency conversion is a pathway to unlock undiscovered physics and implement tailored light sources for spectroscopy or medicine.A key challenge is the establishment of spectrally flat outputs,which is particularly demanding in the context of soliton-based light conversion at low pump energy.Here,we introduce the concept of controlling nonlinear frequency conversion by longitudinally varying resonances,allowing the shaping of soliton dynamics and achieving broadband spectra with substantial spectral flatness.Longitudinally varying resonances are realised by nanofilms with gradually changing thicknesses located on the core of an advanced microstructured fibre.Nanofilms with engineered thickness profiles are fabricated by tilted deposition,representing a waveguidecompatible approach to nano-fabrication,and inducing well-controlled resonances into the system,allowing unique dispersion control along the fibre length.Key features and dependencies are examined experimentally,showing improved bandwidth and spectral flatness via multiple dispersive wave generation and dispersionassisted soliton Raman shifts while maintaining excellent pulse-to-pulse stability and coherence in simulations,suggesting the relevance of our findings for basic science as well as tailored light sources.
