The doping evolution of the nodal electron dynamics in the trilayer cuprate superconductor Bi_(2)Sr_(2)Ca_(2)Cu_(3)O_(10+δ)(Bi2223)is investigated using high-resolution laser-based angle-resolved photoemission spectr...The doping evolution of the nodal electron dynamics in the trilayer cuprate superconductor Bi_(2)Sr_(2)Ca_(2)Cu_(3)O_(10+δ)(Bi2223)is investigated using high-resolution laser-based angle-resolved photoemission spectroscopy(ARPES).Bi2223single crystals with different doping levels are prepared by controlled annealing,which cover the underdoped,optimallydoped and overdoped regions.The electronic phase diagram of Bi2223 is established which describes the Tcdependence on the sample doping level.The doping dependence of the nodal Fermi momentum for the outer(OP)and inner(IP)CuO_(2)planes is determined.Charge distribution imbalance between the OP and IP CuO_(2)planes is quantified,showing enhanced disparity with increasing doping.Nodal band dispersions demonstrate a prominent kink at~94 meV in the IP band,attributed to the unique Cu coordination in the IP plane,while a weaker~60 meV kink is observed in the OP band.The nodal Fermi velocity of both OP and IP bands is nearly constant at~1.62 eV·A independent of doping.These results provide important information to understand the origin of high Tcand superconductivity mechanism in high temperature cuprate superconductors.展开更多
We perform systematic thermal conductivity measurements on heavily hole-doped Ba1-xKxFe2As2 single crystals with 0.747 ≤ x ≤ 0.974. At x=0.747, the K0/T is negligible, indicating a nodeless superconducting gap. A sm...We perform systematic thermal conductivity measurements on heavily hole-doped Ba1-xKxFe2As2 single crystals with 0.747 ≤ x ≤ 0.974. At x=0.747, the K0/T is negligible, indicating a nodeless superconducting gap. A small residual linear term K0/T （=0.035 m W.K-2 cm-1） appears at xz0.826, and it increases slowly up to x=0.974, followed by a substantial increase of more than 20 times to of K0/T clearly shows that the nodal gap appears near x surface topology. The small values of K0/T from x=0.826 the pure KFe2As2 （x=1.0）. This doping dependence = 0.8, possibly associated with the change of Fermi to 0.974 are consistent with the Y-shaped nodal s- wave gap recently revealed by angle-resolved photoemission spectroscopy experiments at x=0.9. Furthermore, the substantial increase of K0/T from x=0.974 to 1.0 is inconsistent with a symmetry-imposed d-wave gap in KFe2 As2, and a possible nodal gap structure in KFe2As2 is discussed.展开更多
Subject Code:B01With the support by the National Natural Science Foundation of China,a creative study by the research group led by Prof.Chen Qianwang(陈乾旺)from the University of Science and Technology of China and H...Subject Code:B01With the support by the National Natural Science Foundation of China,a creative study by the research group led by Prof.Chen Qianwang(陈乾旺)from the University of Science and Technology of China and High Magnetic Field Laboratory,Hefei Institutes of Physical Science,Chinese Academy of展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12488201 by X.J.Z.,12374066 by L.Z.,and 12374154 by X.T.L.)the National Key Research and Development Program of China(Grant Nos.2021YFA1401800 by X.J.Z.,2022YFA1604200 by L.Z.,2022YFA1403900 by G.D.L.and 2023YFA1406000by X.T.L.)+3 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB25000000by X.J.Z.)Innovation Program for Quantum Science and Technology(Grant No.2021ZD0301800 by X.J.Z.)the Youth Innovation Promotion Association of CAS(Grant No.Y2021006 by L.Z.)the Synergetic Extreme Condition User Facility(SECUF)。
文摘The doping evolution of the nodal electron dynamics in the trilayer cuprate superconductor Bi_(2)Sr_(2)Ca_(2)Cu_(3)O_(10+δ)(Bi2223)is investigated using high-resolution laser-based angle-resolved photoemission spectroscopy(ARPES).Bi2223single crystals with different doping levels are prepared by controlled annealing,which cover the underdoped,optimallydoped and overdoped regions.The electronic phase diagram of Bi2223 is established which describes the Tcdependence on the sample doping level.The doping dependence of the nodal Fermi momentum for the outer(OP)and inner(IP)CuO_(2)planes is determined.Charge distribution imbalance between the OP and IP CuO_(2)planes is quantified,showing enhanced disparity with increasing doping.Nodal band dispersions demonstrate a prominent kink at~94 meV in the IP band,attributed to the unique Cu coordination in the IP plane,while a weaker~60 meV kink is observed in the OP band.The nodal Fermi velocity of both OP and IP bands is nearly constant at~1.62 eV·A independent of doping.These results provide important information to understand the origin of high Tcand superconductivity mechanism in high temperature cuprate superconductors.
基金Supported by the National Basic Research Program under Grant Nos 2012CB821402 and 2015CB921401the National Natural Science Foundation of China+1 种基金the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher LearningSTCSM of China(No 15XD1500200)
文摘We perform systematic thermal conductivity measurements on heavily hole-doped Ba1-xKxFe2As2 single crystals with 0.747 ≤ x ≤ 0.974. At x=0.747, the K0/T is negligible, indicating a nodeless superconducting gap. A small residual linear term K0/T （=0.035 m W.K-2 cm-1） appears at xz0.826, and it increases slowly up to x=0.974, followed by a substantial increase of more than 20 times to of K0/T clearly shows that the nodal gap appears near x surface topology. The small values of K0/T from x=0.826 the pure KFe2As2 （x=1.0）. This doping dependence = 0.8, possibly associated with the change of Fermi to 0.974 are consistent with the Y-shaped nodal s- wave gap recently revealed by angle-resolved photoemission spectroscopy experiments at x=0.9. Furthermore, the substantial increase of K0/T from x=0.974 to 1.0 is inconsistent with a symmetry-imposed d-wave gap in KFe2 As2, and a possible nodal gap structure in KFe2As2 is discussed.
文摘Subject Code:B01With the support by the National Natural Science Foundation of China,a creative study by the research group led by Prof.Chen Qianwang(陈乾旺)from the University of Science and Technology of China and High Magnetic Field Laboratory,Hefei Institutes of Physical Science,Chinese Academy of
