收获指数是一个重要的农艺性状,甘蓝型油菜的收获指数偏低,有较大的改良空间,研究油菜收获指数的遗传机理对该性状的改良具有重要的指导意义。本研究利用已构建的高密度遗传图谱对由高、低收获指数亲本衍生而来的包含186个株系的重组自...收获指数是一个重要的农艺性状,甘蓝型油菜的收获指数偏低,有较大的改良空间,研究油菜收获指数的遗传机理对该性状的改良具有重要的指导意义。本研究利用已构建的高密度遗传图谱对由高、低收获指数亲本衍生而来的包含186个株系的重组自交系进行收获指数的数量性状位点(quantitative trait locus,QTL)定位,2016—2018连续3年环境及最佳线性无偏预测(best linear unbiased prediction,BLUP)值共定位到12个收获指数相关QTL,分别位于A03、A05、A06、A07、A09、C04和C05_random染色体上,单个QTL解释的表型变异在1.27%~14.20%之间。同时,利用588份重测序自然群体对收获指数性状开展了全基因组关联分析(genome-wide association study,GWAS),2016、2017、2019年及BLUP值共检测到6个显著关联位点,分别位于A09、C01和C03染色体上,其中2019年环境检测到的位于A09上的S9_25882060与S9_25961704重叠,且与2016年环境检测到的位于A09染色体上的S9_24834640位置接近,此外2016年环境下GWAS检测到的位点2016HI(S9_24834640)位于2017年环境下重组自交系群体定位的q2017HI-9区段内。对比前人研究,本研究获得的18个位点中有1个位点与收获指数相关位点重叠,有6个位点与产量相关性状位点接近。结合本课题组已有的转录组测序结果,在QTL区段及显著关联的SNP位点附近筛选出36个重点候选基因,这些基因主要涉及光合作用、跨膜运输、储藏物质合成及转录调控等。这些研究结果为甘蓝型油菜收获指数的遗传改良提供了重要的理论依据。展开更多
Recently, the layered transition metal dichalcogenide 1 T MoTe2 has attracted considerable attention due to its non-saturating magnetoresistance, type-Ⅱ Weyl semimetal properties, superconductivity, and potential can...Recently, the layered transition metal dichalcogenide 1 T MoTe2 has attracted considerable attention due to its non-saturating magnetoresistance, type-Ⅱ Weyl semimetal properties, superconductivity, and potential candidate for twodimensional(2 D) topological insulator in the single-and few-layer limit. Here in this work, we perform systematic transport measurements on thin flakes of MoTe2 prepared by mechanical exfoliation. We find that MoTe2 flakes are superconducting and have an onset superconducting transition temperature Tc up to 5.3 K, which significantly exceeds that of its bulk counterpart. The in-plane upper critical field(Hc2||) is much higher than the Pauli paramagnetic limit, implying that the MoTe2 flakes have Zeeman-protected Ising superconductivity. Furthermore, the Tc and Hc2|| can be tuned by up to 320 mK and 400 mT by applying a gate voltage. Our result indicates that MoTe2 flake is a good candidate for studying exotic superconductivity with nontrivial topological properties.展开更多
We present a systematical study on single crystalline FeSb2 using electrical transport and magnetic torque measurements at low temperatures. Nonlinear magnetic field dependence of Hall resistivity demonstrates a multi...We present a systematical study on single crystalline FeSb2 using electrical transport and magnetic torque measurements at low temperatures. Nonlinear magnetic field dependence of Hall resistivity demonstrates a multi-carrier transport instinct of the electronic transport. Current-controlled negative differential resistance(CC-NDR) observed in currentvoltage characteristics below ～ 7 K is closely associated with the intrinsic transition ～ 5 K of FeSb2, which is, however,mediated by extrinsic current-induced Joule heating effect. The antimony crystallized in a preferred orientation within the FeSb2 lattice in the high-temperature synthesis process leaves its fingerprint in the de Haas-Van Alphen(dHvA) oscillations, and results in the regular angular dependence of the oscillating frequencies. Nevertheless, possible existence of intrinsic non-trivial states cannot be completely ruled out. Our findings call for further theoretical and experimental studies to explore novel physics on flux-free grown FeSb_2 crystals.展开更多
Single-layered zirconium pentatelluride(ZrTe_5)has been predicted to be a large-gap two-dimensional(2D)topological insulator,which has attracted particular attention in topological phase transitions and potential devi...Single-layered zirconium pentatelluride(ZrTe_5)has been predicted to be a large-gap two-dimensional(2D)topological insulator,which has attracted particular attention in topological phase transitions and potential device applications.Herein,we investigated the transport properties in Zras a function of thickness,ranging from a few nm to several hundred nm.We determined that the temperature of the resistivity anomaly peaktends to increase as the thickness decreases.Moreover,at a critical thickness of～40 nm,the dominating carriers in the films change from n-type to p-type.A comprehensive investigation of Shubnikov–de Hass(SdH)oscillations and Hall resistance at variable temperatures revealed a multi-carrier transport tendency in the thin films.We determined the carrier densities and mobilities of two majority carriers using the simplified two-carrier model.The electron carriers can be attributed to the Dirac band with a non-trivial Berry phaseπ,while the hole carriers may originate from surface chemical reaction or unintentional doping during the microfabrication process.It is necessary to encapsulate the Zrin an inert or vacuum environment to potentially achieve a substantial improvement in device quality.展开更多
We report the observation of in-plane anisotropic magnetoresistance and planar Hall effect in non-magnetic HfTe_(5) thin layers.The observed anisotropic magnetoresistance as well as its sign is strongly dependent on t...We report the observation of in-plane anisotropic magnetoresistance and planar Hall effect in non-magnetic HfTe_(5) thin layers.The observed anisotropic magnetoresistance as well as its sign is strongly dependent on the critical resistivity anomaly temperature T_(p).Below T_(p),the anisotropic magnetoresistance is negative with large negative magnetoresistance.When the in-plane magnetic field is perpendicular to the current,the negative longitudinal magnetoresistance reaches its maximum.The negative longitudinal magnetoresistance effect in HfTe_(5) thin layers is dramatically different from that induced by the chiral anomaly as observed in Weyl and Dirac semimetals.One potential underlying origin may be attributed to the reduced spin scattering,which arises from the in-plane magnetic field driven coupling between the top and bottom surface states.Our findings provide valuable insights for the anisotropic magnetoresistance effect in topological electronic systems and the device potential of HfTe5 in spintronics and quantum sensing.展开更多
文摘收获指数是一个重要的农艺性状,甘蓝型油菜的收获指数偏低,有较大的改良空间,研究油菜收获指数的遗传机理对该性状的改良具有重要的指导意义。本研究利用已构建的高密度遗传图谱对由高、低收获指数亲本衍生而来的包含186个株系的重组自交系进行收获指数的数量性状位点(quantitative trait locus,QTL)定位,2016—2018连续3年环境及最佳线性无偏预测(best linear unbiased prediction,BLUP)值共定位到12个收获指数相关QTL,分别位于A03、A05、A06、A07、A09、C04和C05_random染色体上,单个QTL解释的表型变异在1.27%~14.20%之间。同时,利用588份重测序自然群体对收获指数性状开展了全基因组关联分析(genome-wide association study,GWAS),2016、2017、2019年及BLUP值共检测到6个显著关联位点,分别位于A09、C01和C03染色体上,其中2019年环境检测到的位于A09上的S9_25882060与S9_25961704重叠,且与2016年环境检测到的位于A09染色体上的S9_24834640位置接近,此外2016年环境下GWAS检测到的位点2016HI(S9_24834640)位于2017年环境下重组自交系群体定位的q2017HI-9区段内。对比前人研究,本研究获得的18个位点中有1个位点与收获指数相关位点重叠,有6个位点与产量相关性状位点接近。结合本课题组已有的转录组测序结果,在QTL区段及显著关联的SNP位点附近筛选出36个重点候选基因,这些基因主要涉及光合作用、跨膜运输、储藏物质合成及转录调控等。这些研究结果为甘蓝型油菜收获指数的遗传改良提供了重要的理论依据。
基金Project supported by the Guangdong Innovative and Entrepreneurial Research Team Program,China(Grant No.2016ZT06D348)the National Natural Science Foundation of China(Grant No.11874193)the Shenzhen Fundamental Subject Research Program,China(Grant Nos.JCYJ20170817110751776 and JCYJ20170307105434022)
文摘Recently, the layered transition metal dichalcogenide 1 T MoTe2 has attracted considerable attention due to its non-saturating magnetoresistance, type-Ⅱ Weyl semimetal properties, superconductivity, and potential candidate for twodimensional(2 D) topological insulator in the single-and few-layer limit. Here in this work, we perform systematic transport measurements on thin flakes of MoTe2 prepared by mechanical exfoliation. We find that MoTe2 flakes are superconducting and have an onset superconducting transition temperature Tc up to 5.3 K, which significantly exceeds that of its bulk counterpart. The in-plane upper critical field(Hc2||) is much higher than the Pauli paramagnetic limit, implying that the MoTe2 flakes have Zeeman-protected Ising superconductivity. Furthermore, the Tc and Hc2|| can be tuned by up to 320 mK and 400 mT by applying a gate voltage. Our result indicates that MoTe2 flake is a good candidate for studying exotic superconductivity with nontrivial topological properties.
基金supported by Guangdong Innovative and Entrepreneurial Research Team Program,China(Grant No.2016ZT06D348)the National Natural Science Foundation of China(Grant No.11874193)+1 种基金the Shenzhen Fundamental Subject Research Program,China(Grant Nos.JCYJ20170817110751776 and JCYJ20170307105434022)The work at Brookhaven is supported by the US Department of Energy,Office of Basic Energy Sciences as part of the Computational Material Science Program(material synthesis)
文摘We present a systematical study on single crystalline FeSb2 using electrical transport and magnetic torque measurements at low temperatures. Nonlinear magnetic field dependence of Hall resistivity demonstrates a multi-carrier transport instinct of the electronic transport. Current-controlled negative differential resistance(CC-NDR) observed in currentvoltage characteristics below ～ 7 K is closely associated with the intrinsic transition ～ 5 K of FeSb2, which is, however,mediated by extrinsic current-induced Joule heating effect. The antimony crystallized in a preferred orientation within the FeSb2 lattice in the high-temperature synthesis process leaves its fingerprint in the de Haas-Van Alphen(dHvA) oscillations, and results in the regular angular dependence of the oscillating frequencies. Nevertheless, possible existence of intrinsic non-trivial states cannot be completely ruled out. Our findings call for further theoretical and experimental studies to explore novel physics on flux-free grown FeSb_2 crystals.
基金Project supported by Guangdong Innovative and Entrepreneurial Research Team Program(Grant No.2016ZT06D348)Shenzhen Peacock Program(Grant No.KQTD2016022619565991)
文摘Single-layered zirconium pentatelluride(ZrTe_5)has been predicted to be a large-gap two-dimensional(2D)topological insulator,which has attracted particular attention in topological phase transitions and potential device applications.Herein,we investigated the transport properties in Zras a function of thickness,ranging from a few nm to several hundred nm.We determined that the temperature of the resistivity anomaly peaktends to increase as the thickness decreases.Moreover,at a critical thickness of～40 nm,the dominating carriers in the films change from n-type to p-type.A comprehensive investigation of Shubnikov–de Hass(SdH)oscillations and Hall resistance at variable temperatures revealed a multi-carrier transport tendency in the thin films.We determined the carrier densities and mobilities of two majority carriers using the simplified two-carrier model.The electron carriers can be attributed to the Dirac band with a non-trivial Berry phaseπ,while the hole carriers may originate from surface chemical reaction or unintentional doping during the microfabrication process.It is necessary to encapsulate the Zrin an inert or vacuum environment to potentially achieve a substantial improvement in device quality.
基金Supported by the National Key R&D Program(Grant Nos.2017YFB0405703,2017YFA0205004,and 2018YFA0306600)the National Natural Science Foundation of China(Grant Nos.11974327,11474265,11674295,11674024,and 11874193)+2 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.WK2030020032 and WK2340000082)Anhui Initiative in Quantum Information Technologies,and the Shenzhen Fundamental Subject Research Program(Grant No.JCYJ20170817110751776)the USTC Center for Micro and Nanoscale Research and Fabrication。
文摘We report the observation of in-plane anisotropic magnetoresistance and planar Hall effect in non-magnetic HfTe_(5) thin layers.The observed anisotropic magnetoresistance as well as its sign is strongly dependent on the critical resistivity anomaly temperature T_(p).Below T_(p),the anisotropic magnetoresistance is negative with large negative magnetoresistance.When the in-plane magnetic field is perpendicular to the current,the negative longitudinal magnetoresistance reaches its maximum.The negative longitudinal magnetoresistance effect in HfTe_(5) thin layers is dramatically different from that induced by the chiral anomaly as observed in Weyl and Dirac semimetals.One potential underlying origin may be attributed to the reduced spin scattering,which arises from the in-plane magnetic field driven coupling between the top and bottom surface states.Our findings provide valuable insights for the anisotropic magnetoresistance effect in topological electronic systems and the device potential of HfTe5 in spintronics and quantum sensing.
