We report the physical properties, crystalline and magnetic structures of singe crystals of a new layered antiferromagnetic(AFM) material PrPd0.82Bi2. The measurements of magnetic properties and heat capacity indicate...We report the physical properties, crystalline and magnetic structures of singe crystals of a new layered antiferromagnetic(AFM) material PrPd0.82Bi2. The measurements of magnetic properties and heat capacity indicate an AFM phase transition at TN^7K. A large Sommerfeld coefficient of 329.23 m J·mol-1·K-2 is estimated based on the heat capacity data, implying a possible heavy-fermion behavior. The magnetic structure of this compound is investigated by a combined study of neutron powder and single-crystal diffraction. It is found that an A-type AFM structure with magnetic propagation wavevector k =(0 0 0) is formed below TN. The Pr3+ magnetic moment is aligned along the crystallographic c-axis with an ordered moment of 1.694(3) μBat 4K, which is smaller than the effective moment of the free Pr3+ ion of 3.58 μB.PrPd0.82Bi2 can be grown as large as 1 mm×1 cm in area with a layered shape, and is very easy to be cleaved, providing a unique opportunity to study the interplay between magnetism, possible heavy fermions, and superconductivity.展开更多
High-resolution time-and angle-resolved photoemission measurements were conducted on the topological insulator ZrTe_(5).With strong femtosecond photoexcitation,a possible ultrafast phase transition from a weak to a st...High-resolution time-and angle-resolved photoemission measurements were conducted on the topological insulator ZrTe_(5).With strong femtosecond photoexcitation,a possible ultrafast phase transition from a weak to a strong topological insulating phase was experimentally realized by recovering the energy gap inversion in a time scale that was shorter than 0.15 ps.This photoinduced transient strong topological phase can last longer than 2 ps at the highest excitation fluence studied,and it cannot be attributed to the photoinduced heating of electrons or modification of the conduction band filling.Additionally,the measured unoccupied electronic states are consistent with the first-principles calculation based on experimental crystal lattice constants,which favor a strong topological insulating phase.These findings provide new insights into the longstanding controversy about the strong and weak topological properties in ZrTe_(5),and they suggest that many-body effects including electron–electron interactions must be taken into account to understand the equilibrium weak topological insulating phase in ZrTe_(5).展开更多
Spin-orbit coupling is an important ingredient to regulate the many-body physics,especially for many spin liquid candidate materials such as rare-earth magnets and Kitaev materials.The rare-earth chalcogenides NaYbCh_...Spin-orbit coupling is an important ingredient to regulate the many-body physics,especially for many spin liquid candidate materials such as rare-earth magnets and Kitaev materials.The rare-earth chalcogenides NaYbCh_(2)(Ch=O,S,Se)is a congenital frustrating system to exhibit the intrinsic landmark of spin liquid by eliminating both the site disorders between Na+and Yb^(3+)ions with the big ionic size difference and the Dzyaloshinskii-Moriya interaction with the perfect triangular lattice of the Yb^(3+)ions.The temperature versus magnetic-field phase diagram is established by the magnetization,specific heat,and neutron-scattering measurements.Notably,the neutron diffraction spectra and the magnetization curve might provide microscopic evidence for a series of spin configuration for in-plane fields,which include the disordered spin liquid state,120°antiferromagnet,and one-half magnetization state.Furthermore,the ground state is suggested to be a gapless spin liquid from inelastic neutron scattering,and the magnetic field adjusts the spin orbit coupling.Therefore,the strong spin-orbit coupling in the frustrated quantum magnet substantially enriches low-energy spin physics.This rare-earth family could offer a good platform for exploring the quantum spin liquid ground state and quantum magnetic transitions.展开更多
Following publication of this article[1],the page number in ref.55 was incorrect and should have been 10009 rather than 10.In the Author contribution section of this article,the authors get the support from Prof.Gang ...Following publication of this article[1],the page number in ref.55 was incorrect and should have been 10009 rather than 10.In the Author contribution section of this article,the authors get the support from Prof.Gang Chen,so it should be revised as:“QMZ and JM conducted the study.JSL and ZZ grew NaYbS2 polycrystalline samples and single crystals.展开更多
基金National Key Research and Development Program of China(Grant Nos.2017YFA0302901 and 2016YFA0300604)the National Natural Science Foundation of China(Grant No.11774399)+2 种基金Beijing Natural Science Foundation,China(Grant No.Z180008)the K.C.Wong Education Foundation(Grant No.GJTD-2018-01)the DAAD-PPP programme,and the joint German-Sino HGF-OCPC Postdoc Programme.
文摘We report the physical properties, crystalline and magnetic structures of singe crystals of a new layered antiferromagnetic(AFM) material PrPd0.82Bi2. The measurements of magnetic properties and heat capacity indicate an AFM phase transition at TN^7K. A large Sommerfeld coefficient of 329.23 m J·mol-1·K-2 is estimated based on the heat capacity data, implying a possible heavy-fermion behavior. The magnetic structure of this compound is investigated by a combined study of neutron powder and single-crystal diffraction. It is found that an A-type AFM structure with magnetic propagation wavevector k =(0 0 0) is formed below TN. The Pr3+ magnetic moment is aligned along the crystallographic c-axis with an ordered moment of 1.694(3) μBat 4K, which is smaller than the effective moment of the free Pr3+ ion of 3.58 μB.PrPd0.82Bi2 can be grown as large as 1 mm×1 cm in area with a layered shape, and is very easy to be cleaved, providing a unique opportunity to study the interplay between magnetism, possible heavy fermions, and superconductivity.
基金support from the National Key R&D Program of China(Grant Nos.2021YFA1400202 and 2021YFA1401800)the National Natural Science Foundation of China(Grant Nos.12141404 and 11974243)+3 种基金the Natural Science Foundation of Shanghai(Grant Nos.22ZR1479700 and 23XD1422200)support from the China Postdoctoral Science Foundation(Grant No.2022M722108)support from the National Key R&D Program of China(Grant Nos.2022YFA1402400 and 2021YFA1400100)the National Natural Science Foundation of China(Grant No.12074248)。
文摘High-resolution time-and angle-resolved photoemission measurements were conducted on the topological insulator ZrTe_(5).With strong femtosecond photoexcitation,a possible ultrafast phase transition from a weak to a strong topological insulating phase was experimentally realized by recovering the energy gap inversion in a time scale that was shorter than 0.15 ps.This photoinduced transient strong topological phase can last longer than 2 ps at the highest excitation fluence studied,and it cannot be attributed to the photoinduced heating of electrons or modification of the conduction band filling.Additionally,the measured unoccupied electronic states are consistent with the first-principles calculation based on experimental crystal lattice constants,which favor a strong topological insulating phase.These findings provide new insights into the longstanding controversy about the strong and weak topological properties in ZrTe_(5),and they suggest that many-body effects including electron–electron interactions must be taken into account to understand the equilibrium weak topological insulating phase in ZrTe_(5).
基金supported by the Ministry of Science and Technology of China(Grant No.2022YFA1402700,2018YFGH000095)the NSF of China(Grant No.U2032213,11774223,12274186,11774352,11974244,U1832214,and U1932215)+2 种基金the interdisciplinary program Wuhan National High Magnetic Field Center(Grant No.WHMFC 202122)Huazhong University of Science and Technology,and the Research Grants Council of Hong Kong with General Research Fund Grant No.17303819the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB33010100)。
文摘Spin-orbit coupling is an important ingredient to regulate the many-body physics,especially for many spin liquid candidate materials such as rare-earth magnets and Kitaev materials.The rare-earth chalcogenides NaYbCh_(2)(Ch=O,S,Se)is a congenital frustrating system to exhibit the intrinsic landmark of spin liquid by eliminating both the site disorders between Na+and Yb^(3+)ions with the big ionic size difference and the Dzyaloshinskii-Moriya interaction with the perfect triangular lattice of the Yb^(3+)ions.The temperature versus magnetic-field phase diagram is established by the magnetization,specific heat,and neutron-scattering measurements.Notably,the neutron diffraction spectra and the magnetization curve might provide microscopic evidence for a series of spin configuration for in-plane fields,which include the disordered spin liquid state,120°antiferromagnet,and one-half magnetization state.Furthermore,the ground state is suggested to be a gapless spin liquid from inelastic neutron scattering,and the magnetic field adjusts the spin orbit coupling.Therefore,the strong spin-orbit coupling in the frustrated quantum magnet substantially enriches low-energy spin physics.This rare-earth family could offer a good platform for exploring the quantum spin liquid ground state and quantum magnetic transitions.
文摘Following publication of this article[1],the page number in ref.55 was incorrect and should have been 10009 rather than 10.In the Author contribution section of this article,the authors get the support from Prof.Gang Chen,so it should be revised as:“QMZ and JM conducted the study.JSL and ZZ grew NaYbS2 polycrystalline samples and single crystals.