Determining the number of photons in an incident light pulse at room temperature is the ultimate goal of photodetection.Herein,we report a plasmon-strain-coupled tens of photon level phototransistor by integrating mon...Determining the number of photons in an incident light pulse at room temperature is the ultimate goal of photodetection.Herein,we report a plasmon-strain-coupled tens of photon level phototransistor by integrating monolayer MoS_(2)on top of Au nanowire(NW).Within this structure,Au NW can greatly enhance incident light intensity around MoS_(2),and the large tensile strain can reduce the contact energy barrier between MoS_(2)and Au NW,so as to achieve efficient injection of plasmonic hot electrons into MoS_(2).Furthermore,ultrashort MoS_(2)channel significantly shortens the carrier transit time.As a result,the phototransistor with record optical gain(3.1×10^(11))can accurately determine Poissonian emission statistics of light source with tens of photon level resolution at room temperature.In addition,the phototransistor also demonstrates a broadband spectral sensitivity(0.37–1.55μm),as well as intrinsic photon-polarization selection.Furthermore,an ultra-sensitive optical immunoassay(USOIA)platform is proposed using the phototransistor as photodetector.Coupled with specific antibody-conjugated quantum dot nanospheres and magnetic beads,the platform is able to detect the model biomarker,C-reactive protein,as low as 1.684 amol/L in serum samples with a dynamic range spanning 12 orders of magnitude.With its significantly enhanced sensitivity and simplicity,ultra-high-gain MoS_(2)phototransistor can pave the way toward optically ultra-sensitive determination of various biomarkers for early disease diagnosis.展开更多
基金supported by the National Key Research and Development Program of the Ministry of Science and Technology(2023YFA0915602)the Creative Research Groups Program of the National Natural Science Foundation of China(62321003)+8 种基金the National Natural Science Foundation of China(62134001,U24A20302,62134001,12174094,62274060,62311540157,32271519,and 62274059)the Natural Science Foundation of Hunan Province(2021RC5004)the Science and Technology Innovation Program of Hunan Province(2023RC3112)the Key Research and Development Plan of Hunan Province(2025WK2013)the Guangdong Basic and Applied Basic Research Foundation(2022B1515020029,2022ZDZX2074,and 2024A1515012157)the Shenzhen Science andTechnology Research Funding(JSGG20201103153801005,JCYJ20220818101413029,and ZDSYS20220527171406014)the Shenzhen Medical Research Fund(B2302028)the Key Laboratory of Biomedical Imaging Science and System,Chinese Academy of Sciences,the Key Laboratory of Nanodevices of Jiangsu Province(ZF2302)the Changsha Municipal Natural Science Foundation(kq2402050).
文摘Determining the number of photons in an incident light pulse at room temperature is the ultimate goal of photodetection.Herein,we report a plasmon-strain-coupled tens of photon level phototransistor by integrating monolayer MoS_(2)on top of Au nanowire(NW).Within this structure,Au NW can greatly enhance incident light intensity around MoS_(2),and the large tensile strain can reduce the contact energy barrier between MoS_(2)and Au NW,so as to achieve efficient injection of plasmonic hot electrons into MoS_(2).Furthermore,ultrashort MoS_(2)channel significantly shortens the carrier transit time.As a result,the phototransistor with record optical gain(3.1×10^(11))can accurately determine Poissonian emission statistics of light source with tens of photon level resolution at room temperature.In addition,the phototransistor also demonstrates a broadband spectral sensitivity(0.37–1.55μm),as well as intrinsic photon-polarization selection.Furthermore,an ultra-sensitive optical immunoassay(USOIA)platform is proposed using the phototransistor as photodetector.Coupled with specific antibody-conjugated quantum dot nanospheres and magnetic beads,the platform is able to detect the model biomarker,C-reactive protein,as low as 1.684 amol/L in serum samples with a dynamic range spanning 12 orders of magnitude.With its significantly enhanced sensitivity and simplicity,ultra-high-gain MoS_(2)phototransistor can pave the way toward optically ultra-sensitive determination of various biomarkers for early disease diagnosis.
