A surrounding electromagnetic environment can engineer spontaneous emissions from quantum emitters through the Purcell effect.For instance,a plasmonic antenna can efficiently confine an electromagnetic field and enhan...A surrounding electromagnetic environment can engineer spontaneous emissions from quantum emitters through the Purcell effect.For instance,a plasmonic antenna can efficiently confine an electromagnetic field and enhance the fluorescent process.In this study,we demonstrate that a photonic microcavity can modulate plasmon-enhanced fluorescence by engineering the local electromagnetic environment.Consequently,we constructed a plasmon-enhanced emitter(PE-emitter),which comprised a nanorod and a nanodiamond,using the nanomanipulation technique.Furthermore,we controlled a polystyrene sphere approaching the PE-emitter and investigated in situ the associated fluorescent spectrum and lifetime.The emission of PE-emitter can be enhanced resonantly at the photonic modes as compared to that within the free spectral range.The spectral shape modulated by photonic modes is independent of the separation between the PS sphere and PEemitter.The band integral of the fluorescence decay rate can be enhanced or suppressed after the PS sphere couples to the PE-emitters,depending on the coupling strength between the plasmonic antenna and the photonic cavity.These findings can be utilized in sensing and imaging applications.展开更多
Ultra-confined optical fields are of great importance in fundamental optics and optical technologies.The extreme field confinement in ultra-small nanostructures presents significant challenges in direct near-field cha...Ultra-confined optical fields are of great importance in fundamental optics and optical technologies.The extreme field confinement in ultra-small nanostructures presents significant challenges in direct near-field characterization.Conventional scanning near-field optical microscopy encounters difficulties in characterizing sub-10-nm confined light fields due to significant disturbances of the optical field caused by the probe.Here,by employing a high spatial-resolved photoemission electron microscopy(PEEM),we succeeded in imaging the ultra-confined near fields of a nanoslit mode in a coupled nanowire pair(CNP)with weak disturbance for the first time and demonstrating a quasi-three-dimensional field distribution of the nanoslit mode.We also show that a PEEM image can identify fabrication defects that are influential to the confined field but are imperceptible to many other means.These results open an opportunity for weak-disturbance characterization of ultra-confined optical near fields,which is an essential step toward future optical devices or technology relying on ultra-confined light.展开更多
The on-chip measurement of polarization states plays an increasingly crucial role in modern sensing and imaging applications.While high-performance monolithic linearly polarized photodetectors have been extensively st...The on-chip measurement of polarization states plays an increasingly crucial role in modern sensing and imaging applications.While high-performance monolithic linearly polarized photodetectors have been extensively studied,integrated circularly polarized light(CPL)photodetectors are still hindered by inadequate discrimination capability.This study presents a broadband CPL photodetector utilizing achiral all-dielectric nanostructures,achieving an impressive discrimination ratio of~107 at a wavelength of 405 nm.Our device shows outstanding CPL discrimination capability across the visible band without requiring intensity calibration.It functions based on the CPL-dependent near-field modes within achiral structures:under left or right CPL illumination,distinct near-field modes are excited,resulting in asymmetric irradiation of the two electrodes and generating a photovoltage with directions determined by the chirality of the incident light field.The proposed design strategy facilitates ultra-compact CPL detection across diverse materials,structures,and spectral ranges,presenting a novel avenue for achieving high-performance monolithic CPL detection.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2018YFB2200401)the Major Project of Basic and Applied Basic Research of Guangdong Province,China(Grant No.2020B0301030009)the National Natural Science Foundation of China(Grant Nos.91950111,61521004,and 11527901).
文摘A surrounding electromagnetic environment can engineer spontaneous emissions from quantum emitters through the Purcell effect.For instance,a plasmonic antenna can efficiently confine an electromagnetic field and enhance the fluorescent process.In this study,we demonstrate that a photonic microcavity can modulate plasmon-enhanced fluorescence by engineering the local electromagnetic environment.Consequently,we constructed a plasmon-enhanced emitter(PE-emitter),which comprised a nanorod and a nanodiamond,using the nanomanipulation technique.Furthermore,we controlled a polystyrene sphere approaching the PE-emitter and investigated in situ the associated fluorescent spectrum and lifetime.The emission of PE-emitter can be enhanced resonantly at the photonic modes as compared to that within the free spectral range.The spectral shape modulated by photonic modes is independent of the separation between the PS sphere and PEemitter.The band integral of the fluorescence decay rate can be enhanced or suppressed after the PS sphere couples to the PE-emitters,depending on the coupling strength between the plasmonic antenna and the photonic cavity.These findings can be utilized in sensing and imaging applications.
基金supported by the National Key Research and Development Program of China(2024YFA1209200)the National Natural Science Foundation of China(92250305,92150302,62175213)+1 种基金the New Cornerstone Science Foundation(NCI202216)the Zhejiang Provincial Natural Science Foundation of China(LRG25F050001).
文摘Ultra-confined optical fields are of great importance in fundamental optics and optical technologies.The extreme field confinement in ultra-small nanostructures presents significant challenges in direct near-field characterization.Conventional scanning near-field optical microscopy encounters difficulties in characterizing sub-10-nm confined light fields due to significant disturbances of the optical field caused by the probe.Here,by employing a high spatial-resolved photoemission electron microscopy(PEEM),we succeeded in imaging the ultra-confined near fields of a nanoslit mode in a coupled nanowire pair(CNP)with weak disturbance for the first time and demonstrating a quasi-three-dimensional field distribution of the nanoslit mode.We also show that a PEEM image can identify fabrication defects that are influential to the confined field but are imperceptible to many other means.These results open an opportunity for weak-disturbance characterization of ultra-confined optical near fields,which is an essential step toward future optical devices or technology relying on ultra-confined light.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(Grant No.2020B0301030009)the National Key Research and Development Program of China(Grant No.2022YFA1604304)the National Natural Science Foundation of China(Grant No.92250305).
文摘The on-chip measurement of polarization states plays an increasingly crucial role in modern sensing and imaging applications.While high-performance monolithic linearly polarized photodetectors have been extensively studied,integrated circularly polarized light(CPL)photodetectors are still hindered by inadequate discrimination capability.This study presents a broadband CPL photodetector utilizing achiral all-dielectric nanostructures,achieving an impressive discrimination ratio of~107 at a wavelength of 405 nm.Our device shows outstanding CPL discrimination capability across the visible band without requiring intensity calibration.It functions based on the CPL-dependent near-field modes within achiral structures:under left or right CPL illumination,distinct near-field modes are excited,resulting in asymmetric irradiation of the two electrodes and generating a photovoltage with directions determined by the chirality of the incident light field.The proposed design strategy facilitates ultra-compact CPL detection across diverse materials,structures,and spectral ranges,presenting a novel avenue for achieving high-performance monolithic CPL detection.
