Recently, giant intrinsic anomalous Hall effect(AHE) has been observed in the materials with kagome lattice.Here, we systematically investigate the influence of high pressure on the AHE in the ferromagnet LiMn_(6)Sn_(...Recently, giant intrinsic anomalous Hall effect(AHE) has been observed in the materials with kagome lattice.Here, we systematically investigate the influence of high pressure on the AHE in the ferromagnet LiMn_(6)Sn_(6) with clean Mn kagome lattice. Our in situ high-pressure Raman spectroscopy indicates that the crystal structure of LiMn_(6)Sn_(6) maintains a hexagonal phase under high pressures up to 8.51 GPa. The anomalous Hall conductivity(AHC) σ_(xy)^(A) remains around 150 Ω^(-1)·cm^(-1), dominated by the intrinsic mechanism. Combined with theoretical calculations, our results indicate that the stable AHE under pressure in Li Mn_(6)Sn_(6) originates from the robust electronic and magnetic structure.展开更多
As a new type of quantum state of matter hosting low energy relativistic quasiparticles,Weyl semimetals(WSMs)have attracted significant attention for scientific community and potential quantum device applications.In t...As a new type of quantum state of matter hosting low energy relativistic quasiparticles,Weyl semimetals(WSMs)have attracted significant attention for scientific community and potential quantum device applications.In this study,we present a comprehensive investigation of the structural,magnetic,and transport properties of noncentrosymmetric RAl Si(R=Sm,Ce),which have been predicted to be new magnetic WSM candidates.Both samples exhibit nonsaturated magnetoresistance,with about 900%and 80%for Sm Al Si and Ce Al Si,respectively,at temperature of 1.8 K and magnetic field of 9 T.The carrier densities of Sm Al Si and Ce Al Si exhibit remarkable change around magnetic transition temperatures,signifying that the electronic states are sensitive to the magnetic ordering of rare-earth elements.At low temperatures,Sm Al Si reveals prominent Shubnikov–de Haas oscillations associated with the nontrivial Berry phase.High-pressure experiments demonstrate that the magnetic order is robust and survival under high pressure.Our results would yield valuable insights into WSM physics and potentials in applications to next-generation spintronic devices in the RAl Si(R=Sm,Ce)family.展开更多
We report the synthesis and superconducting properties of a layered cage compound Ba_(3)Rh_(4)Ge_(16).Similar to Ba_(3)Ir_(4)Ge_(16),the compound is composed of 2 D networks of cage units,formed by noncubic Rh-Ge buil...We report the synthesis and superconducting properties of a layered cage compound Ba_(3)Rh_(4)Ge_(16).Similar to Ba_(3)Ir_(4)Ge_(16),the compound is composed of 2 D networks of cage units,formed by noncubic Rh-Ge building blocks,in marked contrast to the reported rattling compounds.The electrical resistivity,magnetization,specific heat capacity,andμSR measurements unveiled moderately coupled s-wave superconductivity with a critical temperature T_(c)=7.0 K,the upper critical field μ_(0)H_(c2)(0)~2.5 T,the electron-phonon coupling strength λ_(e-ph)~0.80,and the Ginzburg-Landau parameterκ~7.89.The mass reduction with the substitution of Ir by Rh is believed to be responsible for the enhancement of T_(c) and coupling between the cage and guest atoms.Our results highlight the importance of atomic weight of framework in cage compounds in controlling the λ_(e-ph) strength and T_(c).展开更多
Clathrate-like or caged compounds have attracted great interest owing to their structural flexibility,as well as their fertile physical properties.Here,we report the pressure-induced reemergence of superconductivity i...Clathrate-like or caged compounds have attracted great interest owing to their structural flexibility,as well as their fertile physical properties.Here,we report the pressure-induced reemergence of superconductivity in BaIr2Ge7 and Ba3Ir4Ge16,two new caged superconductors with two-dimensional building blocks of cage structures.After suppression of the ambient-pressure superconducting(SC-I)states,new superconducting(SC-II)states emerge unexpectedly,with Tc increased to a maximum of 4.4 and 4.0 K for BaIr2Ge7 and Ba3Ir4Ge16,respectively.Combined with high-pressure synchrotron x-ray diffraction and Raman measurements,we propose that the reemergence of superconductivity in these caged superconductors can be ascribed to a pressure-induced phonon softening linked to cage shrinkage.展开更多
Cranberry,the fruit of Vaccinium macrocarpon Aiton,is becoming popular all over the world,due to its pleasant taste,nutraceutical value and biological activities.For a long time,98%of its yield has been from America.S...Cranberry,the fruit of Vaccinium macrocarpon Aiton,is becoming popular all over the world,due to its pleasant taste,nutraceutical value and biological activities.For a long time,98%of its yield has been from America.Since being introduced to China as an import in recent decades,cranberry has become a rapid success in the food industry even with the high transportation cost.Recently,V.macrocarpon was cultivated in the Northeast of China,and the area of cultivation has increased dramatically.Therefore,it is important to systematically determine the useful compounds and their activity in this“Made-in-China”cranberry.In the present study,the content of total phenolics,anthocyanins,proanthocyanidins,sugars and organic acids was determined.Our results demonstrated that domestic cranberry is a rich source of phenolics,anthocyanins,proanthocyanidins,sugars and organic acids.Analysis of the chemical composition of an acidic ethanol extract by UPLC-QTOF-MS identified 21 compounds as well as the contents determination of catechin and cyanidin-3-O-glucoside using RPHPLC.Furthermore,cranberry extract was tested for its anti-bacterial activity against five clinically important pathogens,as well as its inhibitory effect on the proliferation and migration of cancer cells in vitro.Our results demonstrated that cranberry produced in Chinese cultivation areas is a rich source of bioactive compounds and exhibited in vitro anti-microbial and anti-tumor activities.Our work provides essential information about the quality of domestic cranberry and facilitates the development of related industries.展开更多
The recent discovery of superconductivity up to 32 K in the pressurized MoBreignites the interest in exploring high-Tc superconductors in transition-metal diborides. Inspired by that work, we turn our attention to the...The recent discovery of superconductivity up to 32 K in the pressurized MoBreignites the interest in exploring high-Tc superconductors in transition-metal diborides. Inspired by that work, we turn our attention to the 5 d transition-metal diborides.Here we systematically investigate the responses of both structural and physical properties of WBand ReBto external pressure,which possess different types of boron layers. Similar to MoB, the pressure-induced superconductivity was also observed in WBabove 60 GPa with a maximum Tcof 15 K at 100 GPa, while no superconductivity was detected in ReBin this pressure range. Interestingly, the structures at ambient pressure for both WBand ReBpersist to high pressure without structural phase transitions. Theoretical calculations suggest that the ratio of flat boron layers in this class of transition-metal diborides may be crucial for the appearance of high Tc. The combined theoretical and experimental results highlight the effect of the geometry of boron layers on superconductivity and shed light on the exploration of novel high-Tcsuperconductors in borides.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 52272265)the National Key R&D Program of China (Grant Nos. 2023YFA1607400 and 2018YFA0704300)+4 种基金the support from the National Natural Science Foundation of China (Grant Nos. 52271016 and 52188101)the support from Analytical Instrumentation Center (# SPST-AIC10112914), SPST, Shanghai Tech Universitythe European Research Council (ERC Advanced Grant No. 742068 ‘TOPMAT’)the DFG through SFB 1143 (Project ID 247310070)the Würzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC2147,Project ID 390858490)。
文摘Recently, giant intrinsic anomalous Hall effect(AHE) has been observed in the materials with kagome lattice.Here, we systematically investigate the influence of high pressure on the AHE in the ferromagnet LiMn_(6)Sn_(6) with clean Mn kagome lattice. Our in situ high-pressure Raman spectroscopy indicates that the crystal structure of LiMn_(6)Sn_(6) maintains a hexagonal phase under high pressures up to 8.51 GPa. The anomalous Hall conductivity(AHC) σ_(xy)^(A) remains around 150 Ω^(-1)·cm^(-1), dominated by the intrinsic mechanism. Combined with theoretical calculations, our results indicate that the stable AHE under pressure in Li Mn_(6)Sn_(6) originates from the robust electronic and magnetic structure.
基金supported by the National Key R&D Program of China(Grant Nos.2018YFA0704300 and 2017YFB0503302)the National Natural Science Foundation of China(Grant Nos.U1932217,11974246,12004252,61771234,and 12004251)+6 种基金the Natural Science Foundation of Shanghai(Grant Nos.19ZR1477300 and 20ZR1436100)the Science and Technology Commission of Shanghai Municipality(Grant Nos.19JC1413900 and YDZX20203100001438)the Shanghai Science and Technology Plan(Grant No.21DZ2260400),the Shanghai Sailing Program(Grant No.21YF1429200)the Interdisciplinary Program of Wuhan National High Magnetic Field Center(Grant No.WHMFC202124)the Beijing National Laboratory for Condensed Matter Physicsthe support from Analytical Instrumentation Center(Grant No.SPST-AIC10112914)Centre for High-resolution Electron Microscopy(ChEM)(Grant No.EM02161943),SPST,Shanghai Tech University。
文摘As a new type of quantum state of matter hosting low energy relativistic quasiparticles,Weyl semimetals(WSMs)have attracted significant attention for scientific community and potential quantum device applications.In this study,we present a comprehensive investigation of the structural,magnetic,and transport properties of noncentrosymmetric RAl Si(R=Sm,Ce),which have been predicted to be new magnetic WSM candidates.Both samples exhibit nonsaturated magnetoresistance,with about 900%and 80%for Sm Al Si and Ce Al Si,respectively,at temperature of 1.8 K and magnetic field of 9 T.The carrier densities of Sm Al Si and Ce Al Si exhibit remarkable change around magnetic transition temperatures,signifying that the electronic states are sensitive to the magnetic ordering of rare-earth elements.At low temperatures,Sm Al Si reveals prominent Shubnikov–de Haas oscillations associated with the nontrivial Berry phase.High-pressure experiments demonstrate that the magnetic order is robust and survival under high pressure.Our results would yield valuable insights into WSM physics and potentials in applications to next-generation spintronic devices in the RAl Si(R=Sm,Ce)family.
基金Supported the National Key R&D Program of China(Grant No.2018YFA0704300)the National Natural Science Foundation of China(Grant Nos.U1932217,11974246,and 12004252)+5 种基金the Natural Science Foundation of Shanghai(Grant No.19ZR1477300)the Science and Technology Commission of Shanghai Municipality(Grant No.19JC1413900)the Analytical Instrumentation Center,SPST,Shanghai Tech University(Grant No.SPST-AIC10112914)the SERB,India for Core Research grant supportUK-India Newton Funding for funding supportthe Royal Society of London for Newton Advanced Fellowship funding and International Exchange funding between UK and JapanISIS Facility for beam time(Grant No.RB1968041)。
文摘We report the synthesis and superconducting properties of a layered cage compound Ba_(3)Rh_(4)Ge_(16).Similar to Ba_(3)Ir_(4)Ge_(16),the compound is composed of 2 D networks of cage units,formed by noncubic Rh-Ge building blocks,in marked contrast to the reported rattling compounds.The electrical resistivity,magnetization,specific heat capacity,andμSR measurements unveiled moderately coupled s-wave superconductivity with a critical temperature T_(c)=7.0 K,the upper critical field μ_(0)H_(c2)(0)~2.5 T,the electron-phonon coupling strength λ_(e-ph)~0.80,and the Ginzburg-Landau parameterκ~7.89.The mass reduction with the substitution of Ir by Rh is believed to be responsible for the enhancement of T_(c) and coupling between the cage and guest atoms.Our results highlight the importance of atomic weight of framework in cage compounds in controlling the λ_(e-ph) strength and T_(c).
基金the National Natural Science Foundation of China(Grant Nos.U1932217,11974246,and 12004252)the National Key R&D Program of China(Grant No.2018YFA0704300)+3 种基金the Natural Science Foundation of Shanghai(Grant No.19ZR1477300)the Science and Technology Commission of Shanghai Municipality(Grant No.19JC1413900)the Shanghai Science and Technology Plan(Grant No.21DZ2260400)the Analytical Instrumentation Center(Grant No.SPST-AIC10112914),SPST,ShanghaiTech University.
文摘Clathrate-like or caged compounds have attracted great interest owing to their structural flexibility,as well as their fertile physical properties.Here,we report the pressure-induced reemergence of superconductivity in BaIr2Ge7 and Ba3Ir4Ge16,two new caged superconductors with two-dimensional building blocks of cage structures.After suppression of the ambient-pressure superconducting(SC-I)states,new superconducting(SC-II)states emerge unexpectedly,with Tc increased to a maximum of 4.4 and 4.0 K for BaIr2Ge7 and Ba3Ir4Ge16,respectively.Combined with high-pressure synchrotron x-ray diffraction and Raman measurements,we propose that the reemergence of superconductivity in these caged superconductors can be ascribed to a pressure-induced phonon softening linked to cage shrinkage.
基金This study was financially supported by“Liaoning Provincial Engineering Platform of the Development and Utilization of Endangered and Geo-authentic Medicinal Herbs”and“Propagation of Cranberry and the Establishment of Germplasm Resource Nursery(YZ2018ZR01)”.
文摘Cranberry,the fruit of Vaccinium macrocarpon Aiton,is becoming popular all over the world,due to its pleasant taste,nutraceutical value and biological activities.For a long time,98%of its yield has been from America.Since being introduced to China as an import in recent decades,cranberry has become a rapid success in the food industry even with the high transportation cost.Recently,V.macrocarpon was cultivated in the Northeast of China,and the area of cultivation has increased dramatically.Therefore,it is important to systematically determine the useful compounds and their activity in this“Made-in-China”cranberry.In the present study,the content of total phenolics,anthocyanins,proanthocyanidins,sugars and organic acids was determined.Our results demonstrated that domestic cranberry is a rich source of phenolics,anthocyanins,proanthocyanidins,sugars and organic acids.Analysis of the chemical composition of an acidic ethanol extract by UPLC-QTOF-MS identified 21 compounds as well as the contents determination of catechin and cyanidin-3-O-glucoside using RPHPLC.Furthermore,cranberry extract was tested for its anti-bacterial activity against five clinically important pathogens,as well as its inhibitory effect on the proliferation and migration of cancer cells in vitro.Our results demonstrated that cranberry produced in Chinese cultivation areas is a rich source of bioactive compounds and exhibited in vitro anti-microbial and anti-tumor activities.Our work provides essential information about the quality of domestic cranberry and facilitates the development of related industries.
基金supported by the National Natural Science Foundation of China(12004252,52272265,U1932217,11974246,52072400,52025025,and 92065109)the National Key R&D Program of China(2018YFA0704300,2021YFA1401800,2018YFE0202601,2020YFA0308800,and 2022YFA1403400)+2 种基金Shanghai Science and Technology Plan(21DZ2260400)Beijing Natural Science Foundation(Z190010,Z210006,and Z190006)the support from the Analytical Instrumentation Center(#SPST-AIC10112914),School of Physical Science and Technology(SPST),ShanghaiTech University。
基金supported by the National Key R&D Program of China(Grant Nos.2018YFA0704300,2018YFE0202600,and 2017YFA0302903)the National Natural Science Foundation of China(Grant Nos.U1932217,11974246,12004252,12174443,and 11774424)+5 种基金the Natural Science Foundation of Shanghai(Grant No.19ZR1477300)the Science and Technology Commission of Shanghai Municipality(Grant No.19JC1413900)the Shanghai Science and Technology Plan(Grant No.21DZ2260400)the Beijing Natural Science Foundation(Grant No.Z200005)the Fundamental Research Funds for the Central Universities and Research Funds of Renmin University of China(RUC)(Grant Nos.18XNLG14,19XNLG13,19XNLG17,and 22XNKJ40)support from Analytical Instrumentation Center(Grant No.SPSTAIC10112914),SPST,Shanghai Tech University。
文摘The recent discovery of superconductivity up to 32 K in the pressurized MoBreignites the interest in exploring high-Tc superconductors in transition-metal diborides. Inspired by that work, we turn our attention to the 5 d transition-metal diborides.Here we systematically investigate the responses of both structural and physical properties of WBand ReBto external pressure,which possess different types of boron layers. Similar to MoB, the pressure-induced superconductivity was also observed in WBabove 60 GPa with a maximum Tcof 15 K at 100 GPa, while no superconductivity was detected in ReBin this pressure range. Interestingly, the structures at ambient pressure for both WBand ReBpersist to high pressure without structural phase transitions. Theoretical calculations suggest that the ratio of flat boron layers in this class of transition-metal diborides may be crucial for the appearance of high Tc. The combined theoretical and experimental results highlight the effect of the geometry of boron layers on superconductivity and shed light on the exploration of novel high-Tcsuperconductors in borides.