The invention of the Internet and mobile devices has caused tremendous changes in human lives over the past two decades. Information technology has broken through limitations of geospatial space, enabling extremely hi...The invention of the Internet and mobile devices has caused tremendous changes in human lives over the past two decades. Information technology has broken through limitations of geospatial space, enabling extremely high-speed data transmission and new types of data services. In recent years, demands for data processing have shown an increasing trend. Furthermore, data generated from internet-related applications such as cloud services and self-driving technology are likely to grow exponentially over the coming years. Currently, data transmission inside integrated circuits mainly relies on metal wires. However, the substantial resistive–capacitive delay and energy loss that are caused by metal wires limit data transmission speeds. Optical interconnection has been regarded as a major solution to efficiently reduce energy consumption and increase data transmission speeds. The size of conventional semiconductor laser devices, which are the key component in optical interconnection, cannot be smaller than the wavelength of light, which is a fundamental physical obstacle to lasers integrating with current electronic integrated circuits in reasonable volumes. To realize optical interconnection, the volume of the laser device must match the existing electronic components. Recently, the use of diffraction-unlimited plasmonic lasers has been successfully demonstrated, and these have great potential in different applications. In this paper, we discuss the recent progress toward surface plasmon polariton lasers and provide practical insights into the challenges in realizing these novel devices.展开更多
As the combination of surface plasmon polariton and femtosecond laser pulse,femtosecond surface plasmon polariton has both nanoscale spatial resolution and femtosecond temporal resolution,and thus provides promising m...As the combination of surface plasmon polariton and femtosecond laser pulse,femtosecond surface plasmon polariton has both nanoscale spatial resolution and femtosecond temporal resolution,and thus provides promising methods for light field manipulation and light-matter interaction in extreme small spatiotemporal scales.Nowadays,the research on femtosecond surface plasmon polariton is mainly concentrated on two aspects:one is investigation and characterization of excitation,propagation,and dispersion properties of femtosecond surface plasmon polariton in different structures or materials;the other one is developing new applications based on its unique properties in the fields of nonlinear enhancement,pulse shaping,spatiotemporal super-resolved imaging,and others.Here,we introduce the research progress of properties and applications of femtosecond surface plasmon polariton,and prospect its future research trends.With the further development of femtosecond surface plasmon polariton research,it will have a profound impact on nano-optoelectronics,molecular dynamics,biomedicine and other fields.展开更多
High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or micro...High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or microgrooves at relatively higher fluences above 1 J/cm^2.This work aims to enrich the variety of HSFLs-containing hierarchical microstructures,by femtosecond laser(pulse duration:457 fs,wavelength:1045 nm,and repetition rate:100 kHz)in liquids(water and acetone)at laser fluence of 1.7 J/cm^2.The period of Si-HSFLs in the range of 110–200 nm is independent of the scanning speeds(0.1,0.5,1 and 2 mm/s),line intervals(5,15 and 20μm)of scanning lines and scanning directions(perpendicular or parallel to light polarization direction).It is interestingly found that besides normal HSFLs whose orientations are perpendicular to the direction of light polarization,both clockwise or anticlockwise randomly tilted HSFLs with a maximal deviation angle of 50°as compared to those of normal HSFLSs are found on the microstructures with height gradients.Raman spectra and SEM characterization jointly clarify that surface melting and nanocapillary waves play important roles in the formation of Si-HSFLs.The fact that no HSFLs are produced by laser ablation in air indicates that moderate melting facilitated with ultrafast liquid cooling is beneficial for the formation of HSFLs by LALs.On the basis of our findings and previous reports,a synergistic formation mechanism for HSFLs at high fluence was proposed and discussed,including thermal melting with the concomitance of ultrafast cooling in liquids,transformation of the molten layers into ripples and nanotips by surface plasmon polaritons(SPP)and second-harmonic generation(SHG),and modulation of Si-HSFLs direction by both nanocapillary waves and the localized electric field coming from the excited large Si particles.展开更多
Knowledge of surface plasmon polariton （SPP） modes in one-dimensional （1D） metallic nanostructures is essential for the development of subwavelength optical devices such as photonic circuits, integrated light sour...Knowledge of surface plasmon polariton （SPP） modes in one-dimensional （1D） metallic nanostructures is essential for the development of subwavelength optical devices such as photonic circuits, integrated light sources, and photo- detectors. Despite many efforts to characterize the propagation parameters of these subwavelength 1D plasmonic waveguides, such as Ag nanowires, large discrepancies exist among available reports owing to their sensitivity to the relative weights of co-existing SPP modes and the lack of a method of decoupling these modes and analyzing them separately. In this work, we develop an interference method to distinguish different SPP modes that are simultaneously excited in a Ag nanowire waveguide and measure their propagation parameters separately. By extracting information from the propagation-distance- dependent intensity oscillations of the scattered light from the nanowire tip, the effective refractive indices, propagation lengths, and relative mode weights of co-existing SPP modes supported by the nanowire are derived from a mode interference model. These parameters depend strongly on the nanowire diameter and excitation wavelength. In particular, we demonstrate the possibility of selective excitation of different SPP modes by varying the nanowire diameter. This new mode analysis technique provides unique insights into the develop- ment and optimization of SPP-based applications.展开更多
基金Project supported by Grant Nos.MOST 1042221E009096MY3,MOST 1042923E009003MY3,MOST 1032221E019028MY3,MOST 1062917I564021,and MOST 1052221E019049MY3
文摘The invention of the Internet and mobile devices has caused tremendous changes in human lives over the past two decades. Information technology has broken through limitations of geospatial space, enabling extremely high-speed data transmission and new types of data services. In recent years, demands for data processing have shown an increasing trend. Furthermore, data generated from internet-related applications such as cloud services and self-driving technology are likely to grow exponentially over the coming years. Currently, data transmission inside integrated circuits mainly relies on metal wires. However, the substantial resistive–capacitive delay and energy loss that are caused by metal wires limit data transmission speeds. Optical interconnection has been regarded as a major solution to efficiently reduce energy consumption and increase data transmission speeds. The size of conventional semiconductor laser devices, which are the key component in optical interconnection, cannot be smaller than the wavelength of light, which is a fundamental physical obstacle to lasers integrating with current electronic integrated circuits in reasonable volumes. To realize optical interconnection, the volume of the laser device must match the existing electronic components. Recently, the use of diffraction-unlimited plasmonic lasers has been successfully demonstrated, and these have great potential in different applications. In this paper, we discuss the recent progress toward surface plasmon polariton lasers and provide practical insights into the challenges in realizing these novel devices.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.91750205,61427819,U1701661,11674178,and 61975128)the Leading Talents of Guangdong Province Program,China(Grant No.00201505)+2 种基金the Natural Science Foundation of Guangdong Province,China(Grant Nos.2016A030312010 and 2017A030313351)the Science and Technology Innovation Commission of Shenzhen City(Grant Nos.JCYJ20180507182035270,KQTD2017033011044403,KQJSCX20170727100838364,ZDSYS201703031605029,and JCYJ2017818144338999)the K.C.Wong Education Foundation(Grant No.GJTD-2018-08)。
文摘As the combination of surface plasmon polariton and femtosecond laser pulse,femtosecond surface plasmon polariton has both nanoscale spatial resolution and femtosecond temporal resolution,and thus provides promising methods for light field manipulation and light-matter interaction in extreme small spatiotemporal scales.Nowadays,the research on femtosecond surface plasmon polariton is mainly concentrated on two aspects:one is investigation and characterization of excitation,propagation,and dispersion properties of femtosecond surface plasmon polariton in different structures or materials;the other one is developing new applications based on its unique properties in the fields of nonlinear enhancement,pulse shaping,spatiotemporal super-resolved imaging,and others.Here,we introduce the research progress of properties and applications of femtosecond surface plasmon polariton,and prospect its future research trends.With the further development of femtosecond surface plasmon polariton research,it will have a profound impact on nano-optoelectronics,molecular dynamics,biomedicine and other fields.
文摘High spatial frequency laser induced periodic surface structures(HSFLs)on silicon substrates are often developed on flat surfaces at low fluences near ablation threshold of 0.1 J/cm2,seldom on microstructures or microgrooves at relatively higher fluences above 1 J/cm^2.This work aims to enrich the variety of HSFLs-containing hierarchical microstructures,by femtosecond laser(pulse duration:457 fs,wavelength:1045 nm,and repetition rate:100 kHz)in liquids(water and acetone)at laser fluence of 1.7 J/cm^2.The period of Si-HSFLs in the range of 110–200 nm is independent of the scanning speeds(0.1,0.5,1 and 2 mm/s),line intervals(5,15 and 20μm)of scanning lines and scanning directions(perpendicular or parallel to light polarization direction).It is interestingly found that besides normal HSFLs whose orientations are perpendicular to the direction of light polarization,both clockwise or anticlockwise randomly tilted HSFLs with a maximal deviation angle of 50°as compared to those of normal HSFLSs are found on the microstructures with height gradients.Raman spectra and SEM characterization jointly clarify that surface melting and nanocapillary waves play important roles in the formation of Si-HSFLs.The fact that no HSFLs are produced by laser ablation in air indicates that moderate melting facilitated with ultrafast liquid cooling is beneficial for the formation of HSFLs by LALs.On the basis of our findings and previous reports,a synergistic formation mechanism for HSFLs at high fluence was proposed and discussed,including thermal melting with the concomitance of ultrafast cooling in liquids,transformation of the molten layers into ripples and nanotips by surface plasmon polaritons(SPP)and second-harmonic generation(SHG),and modulation of Si-HSFLs direction by both nanocapillary waves and the localized electric field coming from the excited large Si particles.
文摘Knowledge of surface plasmon polariton （SPP） modes in one-dimensional （1D） metallic nanostructures is essential for the development of subwavelength optical devices such as photonic circuits, integrated light sources, and photo- detectors. Despite many efforts to characterize the propagation parameters of these subwavelength 1D plasmonic waveguides, such as Ag nanowires, large discrepancies exist among available reports owing to their sensitivity to the relative weights of co-existing SPP modes and the lack of a method of decoupling these modes and analyzing them separately. In this work, we develop an interference method to distinguish different SPP modes that are simultaneously excited in a Ag nanowire waveguide and measure their propagation parameters separately. By extracting information from the propagation-distance- dependent intensity oscillations of the scattered light from the nanowire tip, the effective refractive indices, propagation lengths, and relative mode weights of co-existing SPP modes supported by the nanowire are derived from a mode interference model. These parameters depend strongly on the nanowire diameter and excitation wavelength. In particular, we demonstrate the possibility of selective excitation of different SPP modes by varying the nanowire diameter. This new mode analysis technique provides unique insights into the develop- ment and optimization of SPP-based applications.
