Undetected-photon imaging allows for objects to be imaged in wavelength regions where traditional components are unavailable. Although first demonstrated using quantum sources, recent work has shown that the technique...Undetected-photon imaging allows for objects to be imaged in wavelength regions where traditional components are unavailable. Although first demonstrated using quantum sources, recent work has shown that the technique also holds with classical beams. To date, however, all the research in this area has exploited parametric downconversion processes using bulk nonlinear crystals within free-space systems. Here, we demonstrate undetectedphoton-based imaging using light generated via stimulated four-wave mixing within highly nonlinear silicon fiber waveguides. The silicon fibers have been tapered to have a core diameter of915 nm to engineer the dispersion and reduce the insertion losses, allowing for tight mode confinement over extended lengths to achieve practical nonlinear conversion efficiencies(-30 dB) with modest pump powers(48 m W). Both amplitude and phase images are obtained using classically generated light, confirming the high degree of spatial and phase correlation of our system. The high powers(>10 nW) and long coherence lengths(>4 km) associated with our large fiber-based system result in high contrast and stable images.展开更多
Light is a union of electric and magnetic fields,and nowhere is the complex relationship between these fields more evident than in the near fields of nanophotonic structures.There,complicated electric and magnetic fie...Light is a union of electric and magnetic fields,and nowhere is the complex relationship between these fields more evident than in the near fields of nanophotonic structures.There,complicated electric and magnetic fields varying over subwavelength scales are generally present,which results in photonic phenomena such as extraordinary optical momentum,superchiral fields,and a complex spatial evolution of optical singularities.An understanding of such phenomena requires nanoscale measurements of the complete optical field vector.Although the sensitivity of nearfield scanning optical microscopy to the complete electromagnetic field was recently demonstrated,a separation of different components required a priori knowledge of the sample.Here,we introduce a robust algorithm that can disentangle all six electric and magnetic field components from a single near-field measurement without any numerical modeling of the structure.As examples,we unravel the fields of two prototypical nanophotonic structures:a photonic crystal waveguide and a plasmonic nanowire.These results pave the way for new studies of complex photonic phenomena at the nanoscale and for the design of structures that optimize their optical behavior.展开更多
基金Engineering and Physical Sciences Research Council(EP/P000940/1)Norges Forskningsrad+2 种基金J.E.Sirrine Textile FoundationNatural Sciences and Engineering Research Council of CanadaNational Natural Science Foundation of China(62175080)
文摘Undetected-photon imaging allows for objects to be imaged in wavelength regions where traditional components are unavailable. Although first demonstrated using quantum sources, recent work has shown that the technique also holds with classical beams. To date, however, all the research in this area has exploited parametric downconversion processes using bulk nonlinear crystals within free-space systems. Here, we demonstrate undetectedphoton-based imaging using light generated via stimulated four-wave mixing within highly nonlinear silicon fiber waveguides. The silicon fibers have been tapered to have a core diameter of915 nm to engineer the dispersion and reduce the insertion losses, allowing for tight mode confinement over extended lengths to achieve practical nonlinear conversion efficiencies(-30 dB) with modest pump powers(48 m W). Both amplitude and phase images are obtained using classically generated light, confirming the high degree of spatial and phase correlation of our system. The high powers(>10 nW) and long coherence lengths(>4 km) associated with our large fiber-based system result in high contrast and stable images.
基金the support from the European Research Council(ERC Advanced Grant 340438-CONSTANS)part of the research program Rubicon with project number 680-50-1513+1 种基金which is partly financed by the Netherlands Organization for Scientific Research(NWO)funded by the Natural Sciences and Engineering Research Council of Canada.
文摘Light is a union of electric and magnetic fields,and nowhere is the complex relationship between these fields more evident than in the near fields of nanophotonic structures.There,complicated electric and magnetic fields varying over subwavelength scales are generally present,which results in photonic phenomena such as extraordinary optical momentum,superchiral fields,and a complex spatial evolution of optical singularities.An understanding of such phenomena requires nanoscale measurements of the complete optical field vector.Although the sensitivity of nearfield scanning optical microscopy to the complete electromagnetic field was recently demonstrated,a separation of different components required a priori knowledge of the sample.Here,we introduce a robust algorithm that can disentangle all six electric and magnetic field components from a single near-field measurement without any numerical modeling of the structure.As examples,we unravel the fields of two prototypical nanophotonic structures:a photonic crystal waveguide and a plasmonic nanowire.These results pave the way for new studies of complex photonic phenomena at the nanoscale and for the design of structures that optimize their optical behavior.
