In this Letter, we propose the electronic manipulation of localized surface plasmon resonance for active tuning in near-field nanofocusing.We theoretically studied the excited graphene tuning of the nanofocusing field...In this Letter, we propose the electronic manipulation of localized surface plasmon resonance for active tuning in near-field nanofocusing.We theoretically studied the excited graphene tuning of the nanofocusing field in fewlayer graphene(FLG)-based hybrid nanotips.It is revealed that the normalized enhanced electric field can be significantly promoted to more than 300 times.It is also observed that resonant peaks can be unprecedently modified by the electron state of excited graphene that is embedded in the substrate.It shows the possibility of flexible tuning of plasmon resonances via controlling the electron excitation state of graphene for specific advanced near-field nanofocusing applications.展开更多
Electrocatalysis,a form of heterogeneous catalysis,is closely associated with both catalyst properties and the catalyst/electrolyte interfacial microenvironment.Herein,we rationally design and synthesize a unique PdCu...Electrocatalysis,a form of heterogeneous catalysis,is closely associated with both catalyst properties and the catalyst/electrolyte interfacial microenvironment.Herein,we rationally design and synthesize a unique PdCu nano-sea urchins(PdCu NSUs)featured with high-curvature nanotips,by which the interfacial microenvironment is expected to be tailored to the electrocatalytic reactions.PdCu NSUs exhibit excellent activity for ethanol electrooxidation,with a specific activity of 4.11 mA cm^(-2)and a mass activity of 2.24 mAμg_(Pd)^(-1),and a high Faraday efficiency(FE)of 96.4%toward acetic acid.COMSOL finite element simulations confirm that the unique nanotips could induce a local electric field due to the accumulation of positive charges in the nanotips,resulting in enrichment of OH^(-)at the catalyst surface to promote the formation of Pd-OH_(ads),a species required by ethanol dehydrogenation.Furthermore,DFT calculations and in-situ electrochemical Fourier transform infrared spectroscopy discover that the d-band center of Pd significantly downshifts in PdCu alloy,which facilitates the desorption of the produced acetic acid.This work provides a new electrocata lytic material with high-curvature nanotips,and also clarifies how the material morphology,by inducing local electric fields,affects the interfacial microenvironment and thus the catalytic activity and selectivity.展开更多
Purpose-The purpose of this paper is to introduce new implementations for parallel processing applications using bijective systolic networks and the corresponding carbon-based field emission controlled switching.The d...Purpose-The purpose of this paper is to introduce new implementations for parallel processing applications using bijective systolic networks and the corresponding carbon-based field emission controlled switching.The developed implementations are performed in the reversible domain to perform the required bijective parallel computing,where the implementations for parallel computations that utilize the presented field-emission controlled switching and their corresponding m-ary(many-valued)extensions for the use in nano systolic networks are introduced.The first part of the paper presents important fundamentals with regards to systolic computing and carbon-based field emission that will be utilized in the implementations within the second part of the paper.Design/methodology/approach-The introduced systolic systems utilize recent findings in field emission and nano applications to implement the functionality of the basic bijective systolic network.This includes many-valued systolic computing via field emission techniques using carbon-based nanotubes and nanotips.The realization of bijective logic circuits in current and emerging technologies can be very important for various reasons.The reduction of power consumption is a major requirement for the circuit design in future technologies,and thus,the new nano systolic circuits can play an important role in the design of circuits that consume minimal power for future applications such as in low-power signal processing.In addition,the implemented bijective systems can be utilized to implement massive parallel processing and thus obtaining very high processing performance,where the implementation will also utilize the significant size reduction within the nano domain.The extensions of implementations to field emission-based many-valued systolic networks using the introduced bijective nano systolic architectures are also presented.Findings-Novel bijective systolic architectures using nano-based field emission implementations are introduced in this paper,and the implementation using the general scheme of many-valued computing is presented.The carbon-based field emission implementation of nano systolic networks is also introduced.This is accomplished using the introduced field emission carbon-based devices,where field emission from carbon nanotubes and nano-apex carbon fibers is utilized.The implementations of the many-valued bijective systolic networks utilizing the introduced nano-based architectures are also presented.Originality/value-The introduced bijective systolic implementations form new important directions in the systolic realizations using the newly emerging nano-based technologies.The 2-to-1 multiplexer is a basic building block in“switch logic,”where in switch logic,a logic circuit is realized as a combination of switches rather than a combination of logic gates as in the gate logic,which proves to be less costly in synthesizing multiplexer-based wide variety of modern circuits and systems since nano implementations exist in very compact space where carbon-based devices switch reliably using much less power than silicon-based devices.The introduced implementations for nano systolic computation are new and interesting for the design in future nanotechnologies that require optimal design specifications of minimum power consumption and minimum size layout such as in low-power control of autonomous robots and in the adiabatic low-power very-large-scale-integration circuit design for signal processing applications.展开更多
Purpose–The purpose of this paper is to introduce new implementations for parallel processing applications using bijective systolic networks and their corresponding carbon-based field emission controlled switching.Th...Purpose–The purpose of this paper is to introduce new implementations for parallel processing applications using bijective systolic networks and their corresponding carbon-based field emission controlled switching.The developed implementations are performed in the reversible domain to perform the required bijective parallel computing,where the implementations for parallel computations that utilize the presented field-emission controlled switching and their corresponding many-valued(m-ary)extensions for the use in nano systolic networks are introduced.The second part of the paper introduces the implementation of systolic computing using two-to-one controlled switching via carbon-based field emission that were presented in the first part of the paper,and the computational extension to the general case of many-valued(m-ary)systolic networks utilizing many-to-one carbon-based field emission is also introduced.Design/methodology/approach–The introduced systolic systems utilize recent findings in field emission and nano applications to implement the functionality of the basic bijective systolic network.This includes many-valued systolic computing via field-emission techniques using carbon-based nanotubes and nanotips.The realization of bijective logic circuits in current and emerging technologies can be very important for various reasons.The reduction of power consumption is a major requirement for the circuit design in future technologies,and thus,the new nano systolic circuits can play an important role in the design of circuits that consume minimal power for future applications such as in low-power signal processing.In addition,the implemented bijective systems can be utilized to implement massive parallel processing and thus obtaining very high processing performance,where the implementation will also utilize the significant size reduction within the nano domain.The extensions of implementations to field emission-based many-valued systolic networks using the introduced bijective nano systolic architectures are also presented.Findings–Novel bijective systolic architectures using nano-based field emission implementations are introduced in this paper,and the implementation using the general scheme of many-valued computing is presented.The carbon-based field emission implementation of nano systolic networks is also introduced.This is accomplished using the introduced field-emission carbon-based devices,where field emission from carbon nanotubes and nano-apex carbon fibersisutilized.The implementationsof the many-valued bijective systolic networks utilizing the introduced nano-based architectures are also presented.Practical implications–The introduced bijective systolic implementations form new important directions in the systolic realizations using the newly emerging nano-based technologies.The 2-to-1 multiplexer is a basic building block in“switch logic,”where in switch logic,a logic circuit is realized as a combination of switches rather than a combination of logic gates as in the gate logic,which proves to be less costly in synthesizing multiplexer-based wide variety of modern circuits and systems since nano implementations exist in very compact space where carbon-based devices switch reliably using much less power than silicon-based devices.The introduced implementations for nano systolic computation are new and interesting for the design in future nanotechnologies that require optimal design specifications of minimum power consumption and minimum size layout such as in low-power control of autonomous robots and in the adiabatic low-power VLSI circuit design for signal processing applications.Originality/value–The introduced bijective systolic implementations form new important directions in the systolic realizations utilizing the newly emerging nanotechnologies.The introduced implementations for nano systolic computation are new and interesting for the design in future nanotechnologies that require optimal design specifications of high performance,minimum power and minimum size.展开更多
This paper reviews an initial achievement of our group toward the development of on-chip parallel high-speed atomic force microscopy（HS-AFM）.A novel AFM approach based on silicon waveguide cantilever displacement se...This paper reviews an initial achievement of our group toward the development of on-chip parallel high-speed atomic force microscopy（HS-AFM）.A novel AFM approach based on silicon waveguide cantilever displacement sensor is proposed.The displacement sensing approach uniquely allows the use of nano-scale wide cantilever that has a high resonance frequency and low spring constant desired for on-chip parallel HS-AFM.The approach consists of low loss silicon waveguide with nano-gap,highly efficient misalignment tolerant coupler,novel high aspect ratio（HAR）sharp nano-tips that can be integrated with nano-scale wide cantilevers and electrostatically driven nano-cantilever actuators.The simulation results show that the displacement sensor with optical power responsivity of 0.31%/nm and AFM cantilever with resonance frequency of 5.4 MHz and spring constant of 0.21 N/m are achievable with the proposed approach.The developed silicon waveguide fabrication method enables silicon waveguide with 6 and 7.5 dB/cm transmission loss for TE and TM modes,respectively,and formation of 13 nm wide nano-gaps between silicon waveguides.The coupler demonstrates misalignment tolerance of ±1.8 μm for 5μm spot size lensed fiber and coupling loss of 2.12 dB/facet for standard cleaved single mode fiber without compromising other performance.The nano-tips with apex radius as small as 2.5 nm and aspect ratio of more than 50 has been enabled by the development of novel HAR nanotip fabrication technique.Integration of the HAR tips onto an array of 460 nm wide cantilever beam has also been demonstrated.展开更多
Terahertz(THz)scattering-type scanning near-field optical microscopy(s-SNOM)is an important means of studying and revealing material properties at the nanoscale.The nanotip is one of the core components of THz s-SNOM,...Terahertz(THz)scattering-type scanning near-field optical microscopy(s-SNOM)is an important means of studying and revealing material properties at the nanoscale.The nanotip is one of the core components of THz s-SNOM,which has a decisive impact on the resolution of the system.In this paper,we focus on the theory and design of the nanotip and conduct comprehensive research on it through simulation.The theoretical model is based on full-wave numerical simulation and dipole moment analysis,which can describe the overall nanotip electromagnetic response under the incident field.A comprehensive design model of nanotip geometry,sample materials,and incident field is established to significantly improve the near-field coupling efficiency and spatial resolution to achieve optimal performance.展开更多
基金supported by the National Key Research and Development Program of China(No.2017YFB1104700)the National Natural Science Foundation of China(Nos.51335008,61775177,and 61475124)+2 种基金the NSAF(No.U1630111)the Collaborative Innovation Center of Suzhou Nano Science and Technologythe China Postdoctoral Science Foundation(No.2014M560778)
文摘In this Letter, we propose the electronic manipulation of localized surface plasmon resonance for active tuning in near-field nanofocusing.We theoretically studied the excited graphene tuning of the nanofocusing field in fewlayer graphene(FLG)-based hybrid nanotips.It is revealed that the normalized enhanced electric field can be significantly promoted to more than 300 times.It is also observed that resonant peaks can be unprecedently modified by the electron state of excited graphene that is embedded in the substrate.It shows the possibility of flexible tuning of plasmon resonances via controlling the electron excitation state of graphene for specific advanced near-field nanofocusing applications.
基金financially supported by the Major Fundamental Research of Natural Science Foundation of Shandong Province(ZR2022ZD10)National Natural Science Foundation of China(22478211,22372017)+2 种基金Postdoctoral Fellowship Program of CPSF(GZC20231193)Liaoning Binhai Laboratory(LBLG-2024-10)Qingdao Postdoctoral Applied Research Project(QDBSH20240102068)。
文摘Electrocatalysis,a form of heterogeneous catalysis,is closely associated with both catalyst properties and the catalyst/electrolyte interfacial microenvironment.Herein,we rationally design and synthesize a unique PdCu nano-sea urchins(PdCu NSUs)featured with high-curvature nanotips,by which the interfacial microenvironment is expected to be tailored to the electrocatalytic reactions.PdCu NSUs exhibit excellent activity for ethanol electrooxidation,with a specific activity of 4.11 mA cm^(-2)and a mass activity of 2.24 mAμg_(Pd)^(-1),and a high Faraday efficiency(FE)of 96.4%toward acetic acid.COMSOL finite element simulations confirm that the unique nanotips could induce a local electric field due to the accumulation of positive charges in the nanotips,resulting in enrichment of OH^(-)at the catalyst surface to promote the formation of Pd-OH_(ads),a species required by ethanol dehydrogenation.Furthermore,DFT calculations and in-situ electrochemical Fourier transform infrared spectroscopy discover that the d-band center of Pd significantly downshifts in PdCu alloy,which facilitates the desorption of the produced acetic acid.This work provides a new electrocata lytic material with high-curvature nanotips,and also clarifies how the material morphology,by inducing local electric fields,affects the interfacial microenvironment and thus the catalytic activity and selectivity.
基金This research was performed during sabbatical leave in 2015-2016 granted to the author from The University of Jordan and spent at Philadelphia University.
文摘Purpose-The purpose of this paper is to introduce new implementations for parallel processing applications using bijective systolic networks and the corresponding carbon-based field emission controlled switching.The developed implementations are performed in the reversible domain to perform the required bijective parallel computing,where the implementations for parallel computations that utilize the presented field-emission controlled switching and their corresponding m-ary(many-valued)extensions for the use in nano systolic networks are introduced.The first part of the paper presents important fundamentals with regards to systolic computing and carbon-based field emission that will be utilized in the implementations within the second part of the paper.Design/methodology/approach-The introduced systolic systems utilize recent findings in field emission and nano applications to implement the functionality of the basic bijective systolic network.This includes many-valued systolic computing via field emission techniques using carbon-based nanotubes and nanotips.The realization of bijective logic circuits in current and emerging technologies can be very important for various reasons.The reduction of power consumption is a major requirement for the circuit design in future technologies,and thus,the new nano systolic circuits can play an important role in the design of circuits that consume minimal power for future applications such as in low-power signal processing.In addition,the implemented bijective systems can be utilized to implement massive parallel processing and thus obtaining very high processing performance,where the implementation will also utilize the significant size reduction within the nano domain.The extensions of implementations to field emission-based many-valued systolic networks using the introduced bijective nano systolic architectures are also presented.Findings-Novel bijective systolic architectures using nano-based field emission implementations are introduced in this paper,and the implementation using the general scheme of many-valued computing is presented.The carbon-based field emission implementation of nano systolic networks is also introduced.This is accomplished using the introduced field emission carbon-based devices,where field emission from carbon nanotubes and nano-apex carbon fibers is utilized.The implementations of the many-valued bijective systolic networks utilizing the introduced nano-based architectures are also presented.Originality/value-The introduced bijective systolic implementations form new important directions in the systolic realizations using the newly emerging nano-based technologies.The 2-to-1 multiplexer is a basic building block in“switch logic,”where in switch logic,a logic circuit is realized as a combination of switches rather than a combination of logic gates as in the gate logic,which proves to be less costly in synthesizing multiplexer-based wide variety of modern circuits and systems since nano implementations exist in very compact space where carbon-based devices switch reliably using much less power than silicon-based devices.The introduced implementations for nano systolic computation are new and interesting for the design in future nanotechnologies that require optimal design specifications of minimum power consumption and minimum size layout such as in low-power control of autonomous robots and in the adiabatic low-power very-large-scale-integration circuit design for signal processing applications.
文摘Purpose–The purpose of this paper is to introduce new implementations for parallel processing applications using bijective systolic networks and their corresponding carbon-based field emission controlled switching.The developed implementations are performed in the reversible domain to perform the required bijective parallel computing,where the implementations for parallel computations that utilize the presented field-emission controlled switching and their corresponding many-valued(m-ary)extensions for the use in nano systolic networks are introduced.The second part of the paper introduces the implementation of systolic computing using two-to-one controlled switching via carbon-based field emission that were presented in the first part of the paper,and the computational extension to the general case of many-valued(m-ary)systolic networks utilizing many-to-one carbon-based field emission is also introduced.Design/methodology/approach–The introduced systolic systems utilize recent findings in field emission and nano applications to implement the functionality of the basic bijective systolic network.This includes many-valued systolic computing via field-emission techniques using carbon-based nanotubes and nanotips.The realization of bijective logic circuits in current and emerging technologies can be very important for various reasons.The reduction of power consumption is a major requirement for the circuit design in future technologies,and thus,the new nano systolic circuits can play an important role in the design of circuits that consume minimal power for future applications such as in low-power signal processing.In addition,the implemented bijective systems can be utilized to implement massive parallel processing and thus obtaining very high processing performance,where the implementation will also utilize the significant size reduction within the nano domain.The extensions of implementations to field emission-based many-valued systolic networks using the introduced bijective nano systolic architectures are also presented.Findings–Novel bijective systolic architectures using nano-based field emission implementations are introduced in this paper,and the implementation using the general scheme of many-valued computing is presented.The carbon-based field emission implementation of nano systolic networks is also introduced.This is accomplished using the introduced field-emission carbon-based devices,where field emission from carbon nanotubes and nano-apex carbon fibersisutilized.The implementationsof the many-valued bijective systolic networks utilizing the introduced nano-based architectures are also presented.Practical implications–The introduced bijective systolic implementations form new important directions in the systolic realizations using the newly emerging nano-based technologies.The 2-to-1 multiplexer is a basic building block in“switch logic,”where in switch logic,a logic circuit is realized as a combination of switches rather than a combination of logic gates as in the gate logic,which proves to be less costly in synthesizing multiplexer-based wide variety of modern circuits and systems since nano implementations exist in very compact space where carbon-based devices switch reliably using much less power than silicon-based devices.The introduced implementations for nano systolic computation are new and interesting for the design in future nanotechnologies that require optimal design specifications of minimum power consumption and minimum size layout such as in low-power control of autonomous robots and in the adiabatic low-power VLSI circuit design for signal processing applications.Originality/value–The introduced bijective systolic implementations form new important directions in the systolic realizations utilizing the newly emerging nanotechnologies.The introduced implementations for nano systolic computation are new and interesting for the design in future nanotechnologies that require optimal design specifications of high performance,minimum power and minimum size.
文摘This paper reviews an initial achievement of our group toward the development of on-chip parallel high-speed atomic force microscopy（HS-AFM）.A novel AFM approach based on silicon waveguide cantilever displacement sensor is proposed.The displacement sensing approach uniquely allows the use of nano-scale wide cantilever that has a high resonance frequency and low spring constant desired for on-chip parallel HS-AFM.The approach consists of low loss silicon waveguide with nano-gap,highly efficient misalignment tolerant coupler,novel high aspect ratio（HAR）sharp nano-tips that can be integrated with nano-scale wide cantilevers and electrostatically driven nano-cantilever actuators.The simulation results show that the displacement sensor with optical power responsivity of 0.31%/nm and AFM cantilever with resonance frequency of 5.4 MHz and spring constant of 0.21 N/m are achievable with the proposed approach.The developed silicon waveguide fabrication method enables silicon waveguide with 6 and 7.5 dB/cm transmission loss for TE and TM modes,respectively,and formation of 13 nm wide nano-gaps between silicon waveguides.The coupler demonstrates misalignment tolerance of ±1.8 μm for 5μm spot size lensed fiber and coupling loss of 2.12 dB/facet for standard cleaved single mode fiber without compromising other performance.The nano-tips with apex radius as small as 2.5 nm and aspect ratio of more than 50 has been enabled by the development of novel HAR nanotip fabrication technique.Integration of the HAR tips onto an array of 460 nm wide cantilever beam has also been demonstrated.
基金supported by the National Natural Science Foundation of China(Nos.12061131010 and 12074198).
文摘Terahertz(THz)scattering-type scanning near-field optical microscopy(s-SNOM)is an important means of studying and revealing material properties at the nanoscale.The nanotip is one of the core components of THz s-SNOM,which has a decisive impact on the resolution of the system.In this paper,we focus on the theory and design of the nanotip and conduct comprehensive research on it through simulation.The theoretical model is based on full-wave numerical simulation and dipole moment analysis,which can describe the overall nanotip electromagnetic response under the incident field.A comprehensive design model of nanotip geometry,sample materials,and incident field is established to significantly improve the near-field coupling efficiency and spatial resolution to achieve optimal performance.
