As the COVID-19 pandemic evolves and new variants emerge,the development of more efficient identification approaches of variants is urgent to prevent continuous outbreaks of SARS-CoV-2.Field-effect transistors(FETs)wi...As the COVID-19 pandemic evolves and new variants emerge,the development of more efficient identification approaches of variants is urgent to prevent continuous outbreaks of SARS-CoV-2.Field-effect transistors(FETs)with two-dimensional(2D)materials are viable platforms for the detection of virus nucleic acids(NAs)but cannot yet provide accurate information on NA variations.Herein,2D Indium selenide(InSe)FETs were used to identify SARSCoV-2 variants.The device's mobility and stability were ensured by atomic layer deposition(ALD)of Al_(2)O_(3).The resulting FETs exhibited sub-fM detection limits ranging from 10^(–14)M to 10^(–8)M.The recognition of single-nucleotide variations was achieved within 15 min to enable the fast and direct identification of two core mutations(L452R,R203M)in Delta genomes(p<0.01).Such capability originated from the trap states in oxidized InSe(InSe_(1-x)O_(x))after ALD,resulting in traps-involved carrier transport responsive to the negative charges of NAs.In sum,the proposed approach might highly provide epidemiological information for timely surveillance of the COVID pandemic.展开更多
Surface plasmonic resonance(SPR)has been a corner stone for approaching single molecular detection due to its highsensitivity capability and simple detection mechanism,and has brought major advancements in biomedicine...Surface plasmonic resonance(SPR)has been a corner stone for approaching single molecular detection due to its highsensitivity capability and simple detection mechanism,and has brought major advancements in biomedicine and life science technology.Over decades,the successful integration of SPR with versatile techniques has been demonstrated.However,several crucial limitations have hindered this technique for practical applications,such as long detection time and low overall sensitivity.This review aims to provide a comprehensive summary of existing approaches in enhancing the performance of SPR sensors based on“passive”and“active”methods.Firstly,passive enhancement is discussed from a material aspect,including signal amplification tags and modifications of conventional substrates.Then,the focus is on the most popular active enhancement methods including electrokinetic,optical,magnetic,and acoustic manipulations that are summarized with highlights on their advantageous features and ability to concentrate target molecules at the detection sites.Lastly,prospects and future development directions for developing SPR sensing towards a more practical,single molecular detection technique in the next generation are discussed.This review hopes to inspire researchers’interests in developing SPR-related technology with more innovative and influential ideas.展开更多
Mercury is a promising candidate for the optical lattice clock, due to its low sensitivity to the blackbody radiation. We develop a single folded beam magneto-optical trap for the neutral mercury optical lattice clock...Mercury is a promising candidate for the optical lattice clock, due to its low sensitivity to the blackbody radiation. We develop a single folded beam magneto-optical trap for the neutral mercury optical lattice clock, with a 253. 7nm frequency quadrupled laser. Up to 1.7 × 10^6 （202Hg） or 1.5 × 10^6 （199Hg） atoms can be captured, and the atom temperature is lowered to 170μK （202Hg） or 50μK （199Hg）. The cold atom signals of all six rich abundant isotopes are observed in this system.展开更多
We present trapping and cooling of single cesium atoms inside a microcavity by means of an intracavity far-off- resonance trap （FORT）. By the ＇magic＇ wavelength FORT, we achieve state-insensitive single-atom trapp...We present trapping and cooling of single cesium atoms inside a microcavity by means of an intracavity far-off- resonance trap （FORT）. By the ＇magic＇ wavelength FORT, we achieve state-insensitive single-atom trapping and cooling in a microeavity. The cavity transmission of the probe beam strongly coupled to single atoms enables us to continuously observe the intracavity atom trapping. The average atomic localization time inside the bright FORT is about 7ms by introducing cavity cooling with appropriate detuning. This experiment presents great potential in coherent state manipulation for strongly coupled atom photon systems in the context of cavity quantum electrodynamics.展开更多
Based on our work on single cesium atoms trapped in a large-magnetic-gradient vapour-cell magneto-optical trap （MOT）, the signal-to-noise ratio （SNR） is remarkably improved. Also a far-off-resonance optical dipole...Based on our work on single cesium atoms trapped in a large-magnetic-gradient vapour-cell magneto-optical trap （MOT）, the signal-to-noise ratio （SNR） is remarkably improved. Also a far-off-resonance optical dipole trap （FORT） formed by a strongly-focused 1064 nm single frequency Nd：YVO4 laser beam is introduced. One cesium atom is prepared in the MOT, and then it can transfer successfully between the MOT and the FORT which is overlapped with the MOT. Utilizing the effective transfer, the lifetime of single atoms trapped in the FORT is measured to be 6.9± 0.3 s. Thus we provide a system where the atomic qubit can be coherently manipulated.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(92064007,62001224,52131304)the Natural Science Foundation of Jiangsu Province(BK20190476,BK20190457,BZ2020063)the 69th batch of China Postdoctoral Science Foundation(2021M691600).
文摘As the COVID-19 pandemic evolves and new variants emerge,the development of more efficient identification approaches of variants is urgent to prevent continuous outbreaks of SARS-CoV-2.Field-effect transistors(FETs)with two-dimensional(2D)materials are viable platforms for the detection of virus nucleic acids(NAs)but cannot yet provide accurate information on NA variations.Herein,2D Indium selenide(InSe)FETs were used to identify SARSCoV-2 variants.The device's mobility and stability were ensured by atomic layer deposition(ALD)of Al_(2)O_(3).The resulting FETs exhibited sub-fM detection limits ranging from 10^(–14)M to 10^(–8)M.The recognition of single-nucleotide variations was achieved within 15 min to enable the fast and direct identification of two core mutations(L452R,R203M)in Delta genomes(p<0.01).Such capability originated from the trap states in oxidized InSe(InSe_(1-x)O_(x))after ALD,resulting in traps-involved carrier transport responsive to the negative charges of NAs.In sum,the proposed approach might highly provide epidemiological information for timely surveillance of the COVID pandemic.
基金the National Natural Science Foundation of China(No.61905145)Guangdong Natural Science Foundation and Province Project(No.2021A1515011916)Shenzhen Science and Technology R&D and Innovation Foundation(No.JCYJ20200109105608771).
文摘Surface plasmonic resonance(SPR)has been a corner stone for approaching single molecular detection due to its highsensitivity capability and simple detection mechanism,and has brought major advancements in biomedicine and life science technology.Over decades,the successful integration of SPR with versatile techniques has been demonstrated.However,several crucial limitations have hindered this technique for practical applications,such as long detection time and low overall sensitivity.This review aims to provide a comprehensive summary of existing approaches in enhancing the performance of SPR sensors based on“passive”and“active”methods.Firstly,passive enhancement is discussed from a material aspect,including signal amplification tags and modifications of conventional substrates.Then,the focus is on the most popular active enhancement methods including electrokinetic,optical,magnetic,and acoustic manipulations that are summarized with highlights on their advantageous features and ability to concentrate target molecules at the detection sites.Lastly,prospects and future development directions for developing SPR sensing towards a more practical,single molecular detection technique in the next generation are discussed.This review hopes to inspire researchers’interests in developing SPR-related technology with more innovative and influential ideas.
基金Supported by the National Natural Science Foundation of China under Grant No 91436105the National Basic Research Program of China under Grant No 2011CB921504the Research Project of Shanghai Science and Technology Commission under Grant No 09DJ1400700
文摘Mercury is a promising candidate for the optical lattice clock, due to its low sensitivity to the blackbody radiation. We develop a single folded beam magneto-optical trap for the neutral mercury optical lattice clock, with a 253. 7nm frequency quadrupled laser. Up to 1.7 × 10^6 （202Hg） or 1.5 × 10^6 （199Hg） atoms can be captured, and the atom temperature is lowered to 170μK （202Hg） or 50μK （199Hg）. The cold atom signals of all six rich abundant isotopes are observed in this system.
基金Supported by the National Basic Research Program of China under Grant No 2012CB921601the National Natural Science Foundation of China under Grant Nos 11125418,61121064,61275210,61227902 and 91336107
文摘We present trapping and cooling of single cesium atoms inside a microcavity by means of an intracavity far-off- resonance trap （FORT）. By the ＇magic＇ wavelength FORT, we achieve state-insensitive single-atom trapping and cooling in a microeavity. The cavity transmission of the probe beam strongly coupled to single atoms enables us to continuously observe the intracavity atom trapping. The average atomic localization time inside the bright FORT is about 7ms by introducing cavity cooling with appropriate detuning. This experiment presents great potential in coherent state manipulation for strongly coupled atom photon systems in the context of cavity quantum electrodynamics.
基金supported by the National Natural Science Foundation of China (Grant Nos 60578018 and 10434080)the project for excellent research team from the National Natural Science Foundation of China (Grant No 60821004)+4 种基金the Program for New Century Excellent Talents of the Education Ministry of China (Grant No NCET-07-0524)the State Basic Key Research Program of China (Grant No 2006CB921102)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No 20070108003)the Natural Science Foundation of Shanxi Province,China (Grant No 2007011003)the Scientific Research Funds for Returned Scholars Abroad of Shanxi Province,China
文摘Based on our work on single cesium atoms trapped in a large-magnetic-gradient vapour-cell magneto-optical trap （MOT）, the signal-to-noise ratio （SNR） is remarkably improved. Also a far-off-resonance optical dipole trap （FORT） formed by a strongly-focused 1064 nm single frequency Nd：YVO4 laser beam is introduced. One cesium atom is prepared in the MOT, and then it can transfer successfully between the MOT and the FORT which is overlapped with the MOT. Utilizing the effective transfer, the lifetime of single atoms trapped in the FORT is measured to be 6.9± 0.3 s. Thus we provide a system where the atomic qubit can be coherently manipulated.
