Based on the Bethe-Ansatz solution of the one-dimensional Heisenberg model under twist boundary conditions, we study the spectra of the persistent current carried by the low-lying excited states. It is shown that thou...Based on the Bethe-Ansatz solution of the one-dimensional Heisenberg model under twist boundary conditions, we study the spectra of the persistent current carried by the low-lying excited states. It is shown that though the energy spectra of spin-singlet and spin-triplet excitations are degenerate, their persistent current spectra are quite different.展开更多
We have successfully synthesized Sr 2 CuO3+δ single crystals under high pressure and high temperature for the first time. The structure analysis show that this material crystallizes into tetragonal structure isostruc...We have successfully synthesized Sr 2 CuO3+δ single crystals under high pressure and high temperature for the first time. The structure analysis show that this material crystallizes into tetragonal structure isostructural La 2 CuO4 with single CuO 2 plane. The magnetic susceptibility as well as resistance measurements indicates that the bulk superconductivity with the critical transition temperature 37 K is achieved in the crystal.展开更多
文摘Based on the Bethe-Ansatz solution of the one-dimensional Heisenberg model under twist boundary conditions, we study the spectra of the persistent current carried by the low-lying excited states. It is shown that though the energy spectra of spin-singlet and spin-triplet excitations are degenerate, their persistent current spectra are quite different.
基金supported by the National Natural Science Foundation of China (Grant No. 90921005)the Ministry of Science and Technology of China (Grant Nos. 2009CB929402 and 2011CBA00103)
文摘We have successfully synthesized Sr 2 CuO3+δ single crystals under high pressure and high temperature for the first time. The structure analysis show that this material crystallizes into tetragonal structure isostructural La 2 CuO4 with single CuO 2 plane. The magnetic susceptibility as well as resistance measurements indicates that the bulk superconductivity with the critical transition temperature 37 K is achieved in the crystal.
