We observed sub-picosecond terahertz(THz)pulses generated from an electro-optic quartz plate using femtosecond optical pulses.The time-resolved THz radiation signal clearly indicates two separated THz pulses with oppo...We observed sub-picosecond terahertz(THz)pulses generated from an electro-optic quartz plate using femtosecond optical pulses.The time-resolved THz radiation signal clearly indicates two separated THz pulses with opposite polarity.Based on our results,a model based on optical-to-THz conversion via optical rectification is proposed to describe the twin pulsed THz emission mechanism of the quartz plate.Firstly,the two separated THz pulses are assigned to the forced and free THz pulses,respectively.With an optical pulse serving as an external source in the crystalline quartz,the forced THz pulse is a solution to linear Maxwell's equations and propagates at the velocity of the pump laser pulse,while the free THz pulse propagates with the group velocity in the THz frequency range.Finally,as a non-centrosymmetry material,the THz amplitude exhibits perfect threefold symmetry with respect to the azimuthal angle and twofold symmetry with respect to the pump polarization angle.展开更多
Inspired by biological ion channels,numerous artificial asymmetric ion channels have been synthesized to facilitate the fabrication of ionic circuits.Nevertheless,the creation of biomimetic asymmetric ion channels nec...Inspired by biological ion channels,numerous artificial asymmetric ion channels have been synthesized to facilitate the fabrication of ionic circuits.Nevertheless,the creation of biomimetic asymmetric ion channels necessitates expensive scientific apparatus and intricate material processing procedures,which constrains its advancement within the realm of ionic devices.In this study,we have devised dynamic asymmetric ion channels with mechanical responsiveness by combining polymers of varying elastic modulus along the longitudinal axis of carbon nanotube fiber(CNTF).The ion rectification can be modulated via the disparate response of CNTF-based ion channels to mechanical stress.We have effectively employed these asymmetric ion channels with mechanical sensitivity in the design of a logic gate device,achieving logic operations such as“AND”and“OR”.The conception of these dynamic asymmetric ion channels with mechanical sensitivity offers a straightforward,cost-effective,and versatile approach for generating ion channels,highlighting their potential application in intricate,highly integrated ionic circuits.展开更多
Heterostructures combined by different individual two-dimensional(2D)materials are essential building blocks to realize unique electronic,optoelectronic properties and multifunctional applications.To date,the direct g...Heterostructures combined by different individual two-dimensional(2D)materials are essential building blocks to realize unique electronic,optoelectronic properties and multifunctional applications.To date,the direct growth of 2D/2D atomic van der Waals heterostructures(vdWHs)have been extensively investigated.However,the heterostructures from 2D inorganic molecular crystals and atomic crystals have been rarely reported.Here we report two-step direct epitaxial growth of the inorganic molecular-atomic Sb2O3/WS2 vdWHs.The thickness of Sb2O3 nanosheets on WS2 nanosheets can be tuned by variable growth temperatures.Oriented growth behavior of Sb2O3 on WS2 was determined through statistics.Optical images,Raman spectra,Raman mappings and selected-area electron diffraction(SAED),etc.,reveal that Sb2O3/WS2 heterostructures are vertically stacked with high crystal quality.Electrical transport measurements demonstrate that the heterotransistors based on the heterostructures possess high current on/off ratio of 5 × 10^5,obvious gate-tunable and current rectification output characteristics.Optoelectronic characterizations show that the heterostructures have a clear photoresponse with high responsivity of 16.4 AW.The growth of vdWHs from 2D inorganic molecular-atomic crystals may open up new opportunities in 2D functional electronics and optoelectronics.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2023YFF0719200)the National Natural Science Foundation of China(Grant Nos.62322115,U24A20226,61988102,and 62435010)+1 种基金111 Project(Grant No.D18014)Science and Technology Commission of Shanghai Municipality(Grant Nos.22JC1400200 and 21S31907400)。
文摘We observed sub-picosecond terahertz(THz)pulses generated from an electro-optic quartz plate using femtosecond optical pulses.The time-resolved THz radiation signal clearly indicates two separated THz pulses with opposite polarity.Based on our results,a model based on optical-to-THz conversion via optical rectification is proposed to describe the twin pulsed THz emission mechanism of the quartz plate.Firstly,the two separated THz pulses are assigned to the forced and free THz pulses,respectively.With an optical pulse serving as an external source in the crystalline quartz,the forced THz pulse is a solution to linear Maxwell's equations and propagates at the velocity of the pump laser pulse,while the free THz pulse propagates with the group velocity in the THz frequency range.Finally,as a non-centrosymmetry material,the THz amplitude exhibits perfect threefold symmetry with respect to the azimuthal angle and twofold symmetry with respect to the pump polarization angle.
基金supported by the National Natural Science Foundation of China(Nos.52273305,21975209,52025132,T2241022,21621091,22021001,and 22121001)the 111 Project(Nos.B17027,B16029)+4 种基金the Fundamental Research Funds for the Central Universities(No.20720230037)the National Science Foundation of Fujian Province of China(Nos.2022J02059,2023J05012)Natural Science Foundation of XiamenChina(No.3502Z20227010)the New Cornerstone Science Foundation through the XPLORER PRIZE。
文摘Inspired by biological ion channels,numerous artificial asymmetric ion channels have been synthesized to facilitate the fabrication of ionic circuits.Nevertheless,the creation of biomimetic asymmetric ion channels necessitates expensive scientific apparatus and intricate material processing procedures,which constrains its advancement within the realm of ionic devices.In this study,we have devised dynamic asymmetric ion channels with mechanical responsiveness by combining polymers of varying elastic modulus along the longitudinal axis of carbon nanotube fiber(CNTF).The ion rectification can be modulated via the disparate response of CNTF-based ion channels to mechanical stress.We have effectively employed these asymmetric ion channels with mechanical sensitivity in the design of a logic gate device,achieving logic operations such as“AND”and“OR”.The conception of these dynamic asymmetric ion channels with mechanical sensitivity offers a straightforward,cost-effective,and versatile approach for generating ion channels,highlighting their potential application in intricate,highly integrated ionic circuits.
基金We acknowledge the financial support from the Fundamental Research Funds of the Central Universities(No.531118010112)the Double First-Class University Initiative of Hunan University(No.531109100004)+2 种基金We also acknowledge the support from the National Natural Science Foundation of China(No.751214296)Hunan Key Laboratory of Two-Dimensional Materials(No.801200005)Strategic Priority Research Program of Chinese Academy of Science(No.XDB30000000).
文摘Heterostructures combined by different individual two-dimensional(2D)materials are essential building blocks to realize unique electronic,optoelectronic properties and multifunctional applications.To date,the direct growth of 2D/2D atomic van der Waals heterostructures(vdWHs)have been extensively investigated.However,the heterostructures from 2D inorganic molecular crystals and atomic crystals have been rarely reported.Here we report two-step direct epitaxial growth of the inorganic molecular-atomic Sb2O3/WS2 vdWHs.The thickness of Sb2O3 nanosheets on WS2 nanosheets can be tuned by variable growth temperatures.Oriented growth behavior of Sb2O3 on WS2 was determined through statistics.Optical images,Raman spectra,Raman mappings and selected-area electron diffraction(SAED),etc.,reveal that Sb2O3/WS2 heterostructures are vertically stacked with high crystal quality.Electrical transport measurements demonstrate that the heterotransistors based on the heterostructures possess high current on/off ratio of 5 × 10^5,obvious gate-tunable and current rectification output characteristics.Optoelectronic characterizations show that the heterostructures have a clear photoresponse with high responsivity of 16.4 AW.The growth of vdWHs from 2D inorganic molecular-atomic crystals may open up new opportunities in 2D functional electronics and optoelectronics.
