In this study,multi-resonator coupled metamaterials(MRCMs)with local resonators are proposed to obtain the multiple and wide band gaps.Kinetic models of the MRCMs are established,and the boundary conditions of the uni...In this study,multi-resonator coupled metamaterials(MRCMs)with local resonators are proposed to obtain the multiple and wide band gaps.Kinetic models of the MRCMs are established,and the boundary conditions of the unit cell are obtained with Bloch's theorem.The effects of structural parameters,including the mass of the resonator and the spring stiffness,on the distributions of the band gaps are studied.Furthermore,the frequency domain responses and the time domain responses are calculated for analyzing the structural vibration characteristics and the effects of damping on structural vibration.The results show that the frequency domain response can accurately express the distributions of the band gaps of the MRCMs,and we can increase the number and the width of the band gaps by using the MRCMs for the superior vibration suppression capability.展开更多
With excellent color purity(full-width half maximum(FWHM)<40 nm)and high quantum yield,multiresonance(MR)molecules can harvest both singlet and triplet excitons for highly efficient narrowband organic light-emittin...With excellent color purity(full-width half maximum(FWHM)<40 nm)and high quantum yield,multiresonance(MR)molecules can harvest both singlet and triplet excitons for highly efficient narrowband organic light-emitting diodes(OLEDs)owing to their thermally activated delayed fluorescence(TADF)nature.However,the highly rigid molecular skeleton with the oppositely positioned bo ron and nitrogen in generating MR effects results in the intrinsic difficulties in the solution-processing of MR-OLEDs.Here,we demonstrate a facile strategy to increase the solubility,enhance the efficiencies and modulate emission color of MR-TADF molecules by extending aromatic rings and introducing tert-butyls into the MR backbone.Two MR-TADF emitters with smaller singlet-triplet splitting energies(ΔE~(ST))and larger oscillator strengths were prepared conveniently,and the solution-processed MR-OLEDs were fabricated for the first time,exhibiting efficient bluish-green electroluminescence with narrow FWHM of 32 nm and external quantum efficiency of 16.3%,which are even comparable to the state-of-the-art performances of the vacuum-evaporated devices.These results prove the feasibility of designing efficient solutionprocessible MR molecules,offering important clues in developing high-performance solution-processed MR-OLEDs with high efficiency and color purity.展开更多
Boron−nitrogen doped multiple resonance(BN-MR)emitters,characterized by B−N covalent bonds,offer distinctive advantages as pivotal building blocks for facile access to novel MR emitters featuring narrowband spectra an...Boron−nitrogen doped multiple resonance(BN-MR)emitters,characterized by B−N covalent bonds,offer distinctive advantages as pivotal building blocks for facile access to novel MR emitters featuring narrowband spectra and high efficiency.However,there remains a scarcity of exploration concerning synthetic methods and structural derivations to expand the library of novel BN-MR emitters.Herein,we present the synthesis of a BN-MR emitter,tCz[B−N]N,through a one-pot borylation reaction directed by the amine group,achieving an impressive yield of 94%.The emitter is decorated by incorporating two 3,6-di-tbutylcarbazole(tCz)units into a B−N covalent bond doped BN-MR parent molecule via para-C−π−D and para-N−π−D conjugations.This peripheral decoration strategy enhances the reverse intersystem crossing process and shifts the emission band towards the pure green region,peaking at 526 nm with a narrowband full-width at half maximum(FWHM)of 41 nm.Consequently,organic light emitting diodes(OLEDs)employing this emitter achieved a maximum external quantum efficiency(EQEmax)value of 27.7%,with minimal efficiency roll-off.Even at a practical luminance of 1000 cd·m^(−2),the device maintains a high EQE value of 24.6%.展开更多
Organic light-emitting diodes(OLEDs)have garnered significant attention for their potential in next-generation display technologies,necessitating the development of emitters that combine high efficiency with superior ...Organic light-emitting diodes(OLEDs)have garnered significant attention for their potential in next-generation display technologies,necessitating the development of emitters that combine high efficiency with superior color purity.In this work,an effective approach by integrating spiro-locking motifs and peripheral substitutions is implanted into multiple resonance(MR)frameworks.The rigid and bulky spiro-locking unit suppresses the vibrations and mitigates aggregation tendencies,preserving the narrow full width at half-maximum(FWHM)in doped films.Peripheral substitutions provide a fine tuning of emission to pure green region.This structural design also facilitates a high horizontal dipole ratio,leading to external quantum efficiencies(EQEs)of 29.5%for LL108 and 24.4%for LL125,with FWHMs less than 30 nm.These devices achieved Commission Internationale de l’Éclairage coordinates of(0.20,0.71)and(0.18,0.72)for LL108 and LL125,respectively,closely aligning with the BT.2020 standard for green emission.Sensitized OLEDs exhibit enhanced electroluminescent performance,achieving a maximum EQE of 30.3%and significantly reduced efficiency roll-off.Although a slight decrease in color purity is observed,optimization through the selection of more compatible sensitizers is feasible.Our study underscores the potential of spiro-locking designs in developing efficient,high color-purity green emitters,contributing to the advancement of OLEDs for ultrahigh-definition displays.展开更多
Circularly polarized luminescence(CPL)is of importance to advance science and technology with significant potential applications in information storage,spintronics and optoelectronic devices.Integrating CPL and the em...Circularly polarized luminescence(CPL)is of importance to advance science and technology with significant potential applications in information storage,spintronics and optoelectronic devices.Integrating CPL and the emission mechanism of thermally activated delayed fluorescence(TADF)has attracted considerable attention,because of their 100%internal quantum efficiency in theory and easily modified molecular structures for tunable photo-electrical properties.However,the typical donor-acceptor(D-A)architecture of CP-TADF emitters generally induces a broad emission profile with inferior color purity due to their large structural relaxation under the processes of excitation and emission.Recently,CP-multi-resonance(MR)-TADF emitters that concurrently display CPL activity,narrowband emission and high efficiency are emerging as the most suitable candidates for the next-generation organic light-emitting diode(OLED)display.In this review,the progress of CP-MR-TADF materials is reviewed in terms of the molecular design strategy,the common relationship between the molecular structures and optoelectronic properties,and their OLEDs performance.Finally,the opportunities and challenges in this research topic are discussed.展开更多
Efficient multi-resonance thermally activated delayed fluorescence(MR-TADF)materials hold significant potential for applications in organic light-emitting diodes(OLEDs)and ultra-high-definition displays.However,the st...Efficient multi-resonance thermally activated delayed fluorescence(MR-TADF)materials hold significant potential for applications in organic light-emitting diodes(OLEDs)and ultra-high-definition displays.However,the stringent synthesis conditions and low yields typically associated with these materials pose substantial challenges for their practical applications.In this study,we introduce an innovative strategy that involves peripheral modification with sulfur and selenium atoms for two materials,CFDBNS and CFDBNSe.This approach enables a directed one-shot borylation process,achieving synthesis yields of 66%and 25%,respectively,while also enhancing reverse intersystem crossing rates.Both emitters exhibit ultra-narrowband sky-blue emissions centered around 474 nm,with full width at half maximum(FWHM)values as narrow as 19 nm in dilute toluene solutions,along with high photoluminescence quantum yields of 98%and 99%in doped films,respectively.The OLEDs based on CFDBNS and CFDBNSe display sky-blue emissions with peaks at 476 and 477 nm and exceptionally slender FWHM values of 23 nm.Furthermore,the devices demonstrate remarkable performances,achieving maximum external quantum efficiencies of 24.1%and 27.2%.This work presents a novel and straightforward approach for the incorporation of heavy atoms,facilitating the rapid construction of efficient MR-TADF materials for OLEDs.展开更多
Multiresonance organoboron helicenes are promising narrowband circularly polarized luminescence(CPL)emitters,which,however,still face formidable challenges to balance a large luminescence dissymmetry factor(glum)and a...Multiresonance organoboron helicenes are promising narrowband circularly polarized luminescence(CPL)emitters,which,however,still face formidable challenges to balance a large luminescence dissymmetry factor(glum)and a high luminescence efficiency.Here,two pairs of organoboron enantiomers(P/M-BN[8]H-ICz and P/M-BN[8]H-BO)with the same hetero[8]helicene geometric structures are developed through polycyclization decoration.We find that it is the helicity of helicene electronic structures rather than the geometrical one that determines the molecular dissymmetry property as a larger electronic helicity could enhance the electron-orbital coupling of the helicene structure.Therefore,P/M-BN[8]H-BO who possesses a hetero[8]helicene electronic structure realizes a nearly one-order-of-magnitude higher glum(+2.75/-2.52×10^(-3))and a higher photoluminescence quantum yield(PLQY)of 99%compared with P/M-BN[8]H-ICz bearing only a hetero[6]helicene electronic distribution structure(glum of only+2.41/-2.37×10^(-4)and PLQY of 95%).Moreover,BN[8]H-BO exhibits a narrowband green emission peaking at 538 nm with a full-width at half-maxima of merely 34 nm,narrower than most multiresonance CPL helicenes.The corresponding organic light-emitting diodes simultaneously realize a high external quantum efficiency of 31.7%,an electroluminescence dissymmetry factors(gEL)of+5.23/-5.07×10^(-3),and an extremely long LT95(time to 95%of the initial luminance)of over 731 h at an initial luminance of 1000 cd m^(-2).展开更多
By investigating a stochastic model for intracellular calcium oscillations proposed by Hfer,we have analyzed the transmission behavior of calcium signaling in a one-dimensional two-way coupled hepatocytes system.It ...By investigating a stochastic model for intracellular calcium oscillations proposed by Hfer,we have analyzed the transmission behavior of calcium signaling in a one-dimensional two-way coupled hepatocytes system.It is shown that when the first cell is subjected to the external noise,the output signal-to-noise ratio(SNR) in the cell exhibits two maxima as a function of external noise intensity,indicating the occurrence of stochastic bi-resonance(SBR).It is more important that when cells are coupled together,the resonant behavior in the 1st cell propagates along the chain with different features through the coupling effect.The cells whose locations are comparatively close to or far from the 1st cell can show SBR,while the cells located in the middle position can display stochastic multi-resonance(SMR).Fur-thermore,the number of cells that can show SMR increases with coupling strength enhancing.These results indicate that the cells system may make an effective choice in response to external signaling induced by noise,through the mechanism of SMR by adjusting coupling strength.展开更多
A combined ME composite structure is made of several cylindrical layered composites in series or parallel connection.Due to the cylindrical structure,the combined structure does not need more space.The characteristics...A combined ME composite structure is made of several cylindrical layered composites in series or parallel connection.Due to the cylindrical structure,the combined structure does not need more space.The characteristics of multi-resonance frequencies have been studied.Each resonance frequency of the structure can be adjusted by changing the cylinder diameter of the corresponding cylindrical layered composites.The number of resonance frequencies increases as the number of cylindrical layered composites increases.The multi-resonance frequencies behavior makes these cylindrical layered composite structures suitable for applications in multifuctional devices with multi-frequencies operation.展开更多
Due to narrowband emission and high quantum efficiencies,polycyclic aromatic heterocycles with multi-resonance thermally activated delayed fluorescence(MR-TADF)properties have recently gained considerable attention in...Due to narrowband emission and high quantum efficiencies,polycyclic aromatic heterocycles with multi-resonance thermally activated delayed fluorescence(MR-TADF)properties have recently gained considerable attention in the organic optoelectronic field.Albeit their great promise in the full visible region covering from blue to red,MR-TADF emitters with ultraviolet emission have been rarely reported.Through locking the two ortho-positions of a triphenylamine core by sulfone groups,a simple polycyclic aromatic heterocycle,BTPT,was facilely constructed,exhibiting 368 nm ultraviolet emission with a narrow full width at half maximum(FWHM)of 33 nm.Its neat film exhibited distinct TADF property with a main emission peak at 388 nm.Noteworthily,the enantiomeric crystals of BTPT not only demonstrated significant circularly polarized luminescence(CPL)with large luminescence dissymmetry factor in the 10^(-3) order but also displayed obvious room temperature phosphorescence(RTP).The relationship between this innovative helical unit and unique photophysical properties,including ultraviolet MR-TADF,CPL,and RTP,was reasonably revealed.展开更多
In this study,the multi-peak terahertz metamaterials sensors are designed and fabricated,whose structures are the asymmetrical single split ring(SSR)and three split rings(TSR).The resonant formation and sensing mechan...In this study,the multi-peak terahertz metamaterials sensors are designed and fabricated,whose structures are the asymmetrical single split ring(SSR)and three split rings(TSR).The resonant formation and sensing mechanism of the two structures are investigated by using the finite-difference time-domain(FDTD)method.Vitamin B6(VB6)and its reactants with bovine serum protein(BSA)are tested as the medium,and the sensing experiments of the SSR and TSR are carried out.The experimental and simulation results indicate the consistent law,which is the sensitivity of the resonance in the transverse magnetic(TM)mode is much greater than that in the transverse electric(TE)mode.According to the weighted average method and the law for unequal precision measuring,the quality factor of the resonance is used as the weighting coefficient to calculate the comprehensive evaluation parameter(CEP)of the multi-peak metamaterials sensors in the TE and TM modes based on the experimental data.When the CEP and frequency shifts are as the evaluation parameter in experiments,the law’s variation of the CEP is consistent with that of the frequency shift,indicating that it is feasible to characterize the sensing characteristics of metamaterials with the CEP,which presents simplified characteristics of multi-peak metamaterials at different polarization modes.The method implies that the different influencing factors may be integrated into the CEP with the idea of weight,which promotes the practical application of the metamaterials sensor.The revelation of the sensing law also provides a method for the design of the terahertz metamaterials sensor with the high sensitivity.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.11872313 and11902045)the National Key R&D Program of China(No.2017YFB1102801)+1 种基金the Fundamental Research Fund for the Central Universitiesthe Seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University(No.CX2020107)。
文摘In this study,multi-resonator coupled metamaterials(MRCMs)with local resonators are proposed to obtain the multiple and wide band gaps.Kinetic models of the MRCMs are established,and the boundary conditions of the unit cell are obtained with Bloch's theorem.The effects of structural parameters,including the mass of the resonator and the spring stiffness,on the distributions of the band gaps are studied.Furthermore,the frequency domain responses and the time domain responses are calculated for analyzing the structural vibration characteristics and the effects of damping on structural vibration.The results show that the frequency domain response can accurately express the distributions of the band gaps of the MRCMs,and we can increase the number and the width of the band gaps by using the MRCMs for the superior vibration suppression capability.
基金supported by the National Natural Science Foundation of China(Nos.21772095,91833306,51873159,91956107,61875090 and 21674049)1311 Talents Program of Nanjing University of Posts and Telecommunications(Dingshan),the Six Talent Plan(No.2016XCL050)+3 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD,No.YX030003)China Postdoctoral Science Foundation(No.2020M671460)Jiangsu Planned Projects for Postdoctoral Research Funds(No.20202137)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.46030CX17761)。
文摘With excellent color purity(full-width half maximum(FWHM)<40 nm)and high quantum yield,multiresonance(MR)molecules can harvest both singlet and triplet excitons for highly efficient narrowband organic light-emitting diodes(OLEDs)owing to their thermally activated delayed fluorescence(TADF)nature.However,the highly rigid molecular skeleton with the oppositely positioned bo ron and nitrogen in generating MR effects results in the intrinsic difficulties in the solution-processing of MR-OLEDs.Here,we demonstrate a facile strategy to increase the solubility,enhance the efficiencies and modulate emission color of MR-TADF molecules by extending aromatic rings and introducing tert-butyls into the MR backbone.Two MR-TADF emitters with smaller singlet-triplet splitting energies(ΔE~(ST))and larger oscillator strengths were prepared conveniently,and the solution-processed MR-OLEDs were fabricated for the first time,exhibiting efficient bluish-green electroluminescence with narrow FWHM of 32 nm and external quantum efficiency of 16.3%,which are even comparable to the state-of-the-art performances of the vacuum-evaporated devices.These results prove the feasibility of designing efficient solutionprocessible MR molecules,offering important clues in developing high-performance solution-processed MR-OLEDs with high efficiency and color purity.
基金financial support from the National Natural Science Foundation of China(Nos.52303253 and 52273198)Yunnan Fundamental Research Project(No.202301BF070001-008)the Yunling Scholar Project of"Yunnan Revitalization Talent Support Program".
文摘Boron−nitrogen doped multiple resonance(BN-MR)emitters,characterized by B−N covalent bonds,offer distinctive advantages as pivotal building blocks for facile access to novel MR emitters featuring narrowband spectra and high efficiency.However,there remains a scarcity of exploration concerning synthetic methods and structural derivations to expand the library of novel BN-MR emitters.Herein,we present the synthesis of a BN-MR emitter,tCz[B−N]N,through a one-pot borylation reaction directed by the amine group,achieving an impressive yield of 94%.The emitter is decorated by incorporating two 3,6-di-tbutylcarbazole(tCz)units into a B−N covalent bond doped BN-MR parent molecule via para-C−π−D and para-N−π−D conjugations.This peripheral decoration strategy enhances the reverse intersystem crossing process and shifts the emission band towards the pure green region,peaking at 526 nm with a narrowband full-width at half maximum(FWHM)of 41 nm.Consequently,organic light emitting diodes(OLEDs)employing this emitter achieved a maximum external quantum efficiency(EQEmax)value of 27.7%,with minimal efficiency roll-off.Even at a practical luminance of 1000 cd·m^(−2),the device maintains a high EQE value of 24.6%.
基金supported by the National Natural Science Foundation of China(52373191,52130308)Guangdong Basic and Applied Basic Research Foundation(2023A1515030176)+1 种基金Shenzhen Science and Technology Program(ZDSYS20210623091813040,JCYJ20240813142905007)Research Team Cultivation Program of Shenzhen University(2023DFT004)。
文摘Organic light-emitting diodes(OLEDs)have garnered significant attention for their potential in next-generation display technologies,necessitating the development of emitters that combine high efficiency with superior color purity.In this work,an effective approach by integrating spiro-locking motifs and peripheral substitutions is implanted into multiple resonance(MR)frameworks.The rigid and bulky spiro-locking unit suppresses the vibrations and mitigates aggregation tendencies,preserving the narrow full width at half-maximum(FWHM)in doped films.Peripheral substitutions provide a fine tuning of emission to pure green region.This structural design also facilitates a high horizontal dipole ratio,leading to external quantum efficiencies(EQEs)of 29.5%for LL108 and 24.4%for LL125,with FWHMs less than 30 nm.These devices achieved Commission Internationale de l’Éclairage coordinates of(0.20,0.71)and(0.18,0.72)for LL108 and LL125,respectively,closely aligning with the BT.2020 standard for green emission.Sensitized OLEDs exhibit enhanced electroluminescent performance,achieving a maximum EQE of 30.3%and significantly reduced efficiency roll-off.Although a slight decrease in color purity is observed,optimization through the selection of more compatible sensitizers is feasible.Our study underscores the potential of spiro-locking designs in developing efficient,high color-purity green emitters,contributing to the advancement of OLEDs for ultrahigh-definition displays.
基金supported by the National Key R&D Program of China(2022YFE0104100)the National Natural Science Foundation of China(22205188,52073242)+5 种基金the ITC Guangdong-Hong Kong Technology Cooperation Funding Scheme(TCFS)(GHP/038/19GD)the CAS-Croucher Funding Scheme for Joint Laboratories(ZH4A)the Hong Kong Research Grants Council(Poly U 15305320)the Hong Kong Polytechnic University(YXB8 and W19V)the Miss Clarea Au for the Endowed Professorship in Energy(847S)the Research Institute for Smart Energy(CDAQ)。
文摘Circularly polarized luminescence(CPL)is of importance to advance science and technology with significant potential applications in information storage,spintronics and optoelectronic devices.Integrating CPL and the emission mechanism of thermally activated delayed fluorescence(TADF)has attracted considerable attention,because of their 100%internal quantum efficiency in theory and easily modified molecular structures for tunable photo-electrical properties.However,the typical donor-acceptor(D-A)architecture of CP-TADF emitters generally induces a broad emission profile with inferior color purity due to their large structural relaxation under the processes of excitation and emission.Recently,CP-multi-resonance(MR)-TADF emitters that concurrently display CPL activity,narrowband emission and high efficiency are emerging as the most suitable candidates for the next-generation organic light-emitting diode(OLED)display.In this review,the progress of CP-MR-TADF materials is reviewed in terms of the molecular design strategy,the common relationship between the molecular structures and optoelectronic properties,and their OLEDs performance.Finally,the opportunities and challenges in this research topic are discussed.
基金supported by the National Natural Science Foundation of China(92256304,U23A20593)the Fundamental Research Funds for the Central Universities(020514380294)。
文摘Efficient multi-resonance thermally activated delayed fluorescence(MR-TADF)materials hold significant potential for applications in organic light-emitting diodes(OLEDs)and ultra-high-definition displays.However,the stringent synthesis conditions and low yields typically associated with these materials pose substantial challenges for their practical applications.In this study,we introduce an innovative strategy that involves peripheral modification with sulfur and selenium atoms for two materials,CFDBNS and CFDBNSe.This approach enables a directed one-shot borylation process,achieving synthesis yields of 66%and 25%,respectively,while also enhancing reverse intersystem crossing rates.Both emitters exhibit ultra-narrowband sky-blue emissions centered around 474 nm,with full width at half maximum(FWHM)values as narrow as 19 nm in dilute toluene solutions,along with high photoluminescence quantum yields of 98%and 99%in doped films,respectively.The OLEDs based on CFDBNS and CFDBNSe display sky-blue emissions with peaks at 476 and 477 nm and exceptionally slender FWHM values of 23 nm.Furthermore,the devices demonstrate remarkable performances,achieving maximum external quantum efficiencies of 24.1%and 27.2%.This work presents a novel and straightforward approach for the incorporation of heavy atoms,facilitating the rapid construction of efficient MR-TADF materials for OLEDs.
基金National Key Research and Development Program of China,Grant/Award Number:2023YFB3609100National Natural Science Foundation of China,Grant/Award Number:2240051296+1 种基金National Key Research and Development Program,Grant/Award Numbers:2022YFA1204404,2021YFB3602702Postdoctoral Fellowship Program of CPSF,Grant/Award Number:GZC20231250。
文摘Multiresonance organoboron helicenes are promising narrowband circularly polarized luminescence(CPL)emitters,which,however,still face formidable challenges to balance a large luminescence dissymmetry factor(glum)and a high luminescence efficiency.Here,two pairs of organoboron enantiomers(P/M-BN[8]H-ICz and P/M-BN[8]H-BO)with the same hetero[8]helicene geometric structures are developed through polycyclization decoration.We find that it is the helicity of helicene electronic structures rather than the geometrical one that determines the molecular dissymmetry property as a larger electronic helicity could enhance the electron-orbital coupling of the helicene structure.Therefore,P/M-BN[8]H-BO who possesses a hetero[8]helicene electronic structure realizes a nearly one-order-of-magnitude higher glum(+2.75/-2.52×10^(-3))and a higher photoluminescence quantum yield(PLQY)of 99%compared with P/M-BN[8]H-ICz bearing only a hetero[6]helicene electronic distribution structure(glum of only+2.41/-2.37×10^(-4)and PLQY of 95%).Moreover,BN[8]H-BO exhibits a narrowband green emission peaking at 538 nm with a full-width at half-maxima of merely 34 nm,narrower than most multiresonance CPL helicenes.The corresponding organic light-emitting diodes simultaneously realize a high external quantum efficiency of 31.7%,an electroluminescence dissymmetry factors(gEL)of+5.23/-5.07×10^(-3),and an extremely long LT95(time to 95%of the initial luminance)of over 731 h at an initial luminance of 1000 cd m^(-2).
基金the Research Fund of Anhui Normal University(Grant No.2006xzx09)the Educational Commission of Anhui Province of China(Grant No.KJ2007A079)the Program for Innovative Research Team in Anhui Normal University
文摘By investigating a stochastic model for intracellular calcium oscillations proposed by Hfer,we have analyzed the transmission behavior of calcium signaling in a one-dimensional two-way coupled hepatocytes system.It is shown that when the first cell is subjected to the external noise,the output signal-to-noise ratio(SNR) in the cell exhibits two maxima as a function of external noise intensity,indicating the occurrence of stochastic bi-resonance(SBR).It is more important that when cells are coupled together,the resonant behavior in the 1st cell propagates along the chain with different features through the coupling effect.The cells whose locations are comparatively close to or far from the 1st cell can show SBR,while the cells located in the middle position can display stochastic multi-resonance(SMR).Fur-thermore,the number of cells that can show SMR increases with coupling strength enhancing.These results indicate that the cells system may make an effective choice in response to external signaling induced by noise,through the mechanism of SMR by adjusting coupling strength.
基金supported by the National High Technology Research and Development Program of China(Grant No.2012AA030403)National Natural Science Foundation of China(Grant Nos.51032003,11274198,51102148,51221291)+2 种基金Shandong Natural Science Foundation(Grant No.ZR2010AM025)the China Postdoctoral Research Foundation(Grant No.2013M530042)the Research Fund for the Doctoral Program of Higher Education(Grant No.2010000612003)
文摘A combined ME composite structure is made of several cylindrical layered composites in series or parallel connection.Due to the cylindrical structure,the combined structure does not need more space.The characteristics of multi-resonance frequencies have been studied.Each resonance frequency of the structure can be adjusted by changing the cylinder diameter of the corresponding cylindrical layered composites.The number of resonance frequencies increases as the number of cylindrical layered composites increases.The multi-resonance frequencies behavior makes these cylindrical layered composite structures suitable for applications in multifuctional devices with multi-frequencies operation.
基金supported by the National Natural Science Foundation of China(52022071,52130308,91833304)the Fundamental Research Funds for the Central Universities(2042021kf1060)Shenzhen Science and Technology Program(ZDSYS20210623091813040,JCYJ20190808151209557)。
文摘Due to narrowband emission and high quantum efficiencies,polycyclic aromatic heterocycles with multi-resonance thermally activated delayed fluorescence(MR-TADF)properties have recently gained considerable attention in the organic optoelectronic field.Albeit their great promise in the full visible region covering from blue to red,MR-TADF emitters with ultraviolet emission have been rarely reported.Through locking the two ortho-positions of a triphenylamine core by sulfone groups,a simple polycyclic aromatic heterocycle,BTPT,was facilely constructed,exhibiting 368 nm ultraviolet emission with a narrow full width at half maximum(FWHM)of 33 nm.Its neat film exhibited distinct TADF property with a main emission peak at 388 nm.Noteworthily,the enantiomeric crystals of BTPT not only demonstrated significant circularly polarized luminescence(CPL)with large luminescence dissymmetry factor in the 10^(-3) order but also displayed obvious room temperature phosphorescence(RTP).The relationship between this innovative helical unit and unique photophysical properties,including ultraviolet MR-TADF,CPL,and RTP,was reasonably revealed.
基金The authors are grateful for the financial support from the National Natural Science Foundation of China(NSFC)(Grant Nos.62065005 and 62063003)the Natural Science Foundation of Guangxi(Grant Nos.2021GXNSFBA196081 and 2021AC19093)the Foundation from Guangxi Key Laboratory of Automatic Detection Technology and Instrument(Grant Nos.YQ20116,YQ21109,and YQ19103).
文摘In this study,the multi-peak terahertz metamaterials sensors are designed and fabricated,whose structures are the asymmetrical single split ring(SSR)and three split rings(TSR).The resonant formation and sensing mechanism of the two structures are investigated by using the finite-difference time-domain(FDTD)method.Vitamin B6(VB6)and its reactants with bovine serum protein(BSA)are tested as the medium,and the sensing experiments of the SSR and TSR are carried out.The experimental and simulation results indicate the consistent law,which is the sensitivity of the resonance in the transverse magnetic(TM)mode is much greater than that in the transverse electric(TE)mode.According to the weighted average method and the law for unequal precision measuring,the quality factor of the resonance is used as the weighting coefficient to calculate the comprehensive evaluation parameter(CEP)of the multi-peak metamaterials sensors in the TE and TM modes based on the experimental data.When the CEP and frequency shifts are as the evaluation parameter in experiments,the law’s variation of the CEP is consistent with that of the frequency shift,indicating that it is feasible to characterize the sensing characteristics of metamaterials with the CEP,which presents simplified characteristics of multi-peak metamaterials at different polarization modes.The method implies that the different influencing factors may be integrated into the CEP with the idea of weight,which promotes the practical application of the metamaterials sensor.The revelation of the sensing law also provides a method for the design of the terahertz metamaterials sensor with the high sensitivity.
