The 〈 110 〉 -oriented TTb0.3Dy0.7Fe1.95 polycrystalline alloy was magnetically annealed, and its influence on jump effect of magnetostriction was investigated. In the vacuum superconductive high magnetic field equip...The 〈 110 〉 -oriented TTb0.3Dy0.7Fe1.95 polycrystalline alloy was magnetically annealed, and its influence on jump effect of magnetostriction was investigated. In the vacuum superconductive high magnetic field equipment, 〈 110 〉 -oriented Tb0.3Dy0.7Fe1.95 polycrystalline alloy of the directional solidification was annealed at 623 and 723 K for 5 min under the magnetic field vertical to specimen axis. It is found that magnetic annealing can enhance the jump effect under compressive stress, and increase the saturated magnetostriction coefficient λs, the λs of the magnetic annealing specimens at 623 K under 8.1 MPa is attained to 1950 × 10^-6, Magnetic annealing increases the maximum of dynamic magnetostriction coefficient, d33^max, as well as the magnetic field for d33^max under 8.1 MPa.展开更多
The transport properties in the mixed state of high-quality Ca_(0.8)La_(0.2)Fe_(0.98)Co_(0.02)As_2single crystal,a newly discovered 112-type iron pnictide superconductor,are comprehensively studied by magneto-resistiv...The transport properties in the mixed state of high-quality Ca_(0.8)La_(0.2)Fe_(0.98)Co_(0.02)As_2single crystal,a newly discovered 112-type iron pnictide superconductor,are comprehensively studied by magneto-resistivity measurement.The field-dependent activation energy,U_0,is derived in the framework of thermally activated flux flow(TAFF)theory,yielding a power law dependence U_0～H~αwith a crossover at a magnetic field around 2 T in both H⊥ab and H//ab,which is ascribed to the different pinning mechanisms.Moreover,we have clearly observed the vortex phase transition from vortex-glass to vortex-liquid according to the vortex-glass model,and vortex phase diagrams are constructed for both H⊥ab and H//ab.Finally,the results of mixed-state Hall effect show that no sign reversal of transverse resistivityρ_(xy)(H)is detected,indicating that the Hall component arising from the vortex flow is in theories or experiments previously reported on some high-T_ccuprates.展开更多
文摘The 〈 110 〉 -oriented TTb0.3Dy0.7Fe1.95 polycrystalline alloy was magnetically annealed, and its influence on jump effect of magnetostriction was investigated. In the vacuum superconductive high magnetic field equipment, 〈 110 〉 -oriented Tb0.3Dy0.7Fe1.95 polycrystalline alloy of the directional solidification was annealed at 623 and 723 K for 5 min under the magnetic field vertical to specimen axis. It is found that magnetic annealing can enhance the jump effect under compressive stress, and increase the saturated magnetostriction coefficient λs, the λs of the magnetic annealing specimens at 623 K under 8.1 MPa is attained to 1950 × 10^-6, Magnetic annealing increases the maximum of dynamic magnetostriction coefficient, d33^max, as well as the magnetic field for d33^max under 8.1 MPa.
基金Foundation of China (Grant Nos. 11674054, and 11611140101)XiangZhou Xing was also sponsored by the Scientific Research Foundation of Graduate School of Southeast University (Grant No. YBJJ1621)
文摘The transport properties in the mixed state of high-quality Ca_(0.8)La_(0.2)Fe_(0.98)Co_(0.02)As_2single crystal,a newly discovered 112-type iron pnictide superconductor,are comprehensively studied by magneto-resistivity measurement.The field-dependent activation energy,U_0,is derived in the framework of thermally activated flux flow(TAFF)theory,yielding a power law dependence U_0～H~αwith a crossover at a magnetic field around 2 T in both H⊥ab and H//ab,which is ascribed to the different pinning mechanisms.Moreover,we have clearly observed the vortex phase transition from vortex-glass to vortex-liquid according to the vortex-glass model,and vortex phase diagrams are constructed for both H⊥ab and H//ab.Finally,the results of mixed-state Hall effect show that no sign reversal of transverse resistivityρ_(xy)(H)is detected,indicating that the Hall component arising from the vortex flow is in theories or experiments previously reported on some high-T_ccuprates.
