Proposal of an extended t-J Hamiltonian for high-Tc cuprates from ab initio calculations on embedded clusters
Proposal of an extended t-J Hamiltonian for high-Tc cuprates from ab initio calculations on embedded clusters
复制标题
从嵌入式簇的从头算起提出用于高温铜酸盐的扩展 t-J 哈密顿量
DOI：
10.1103/physrevb.63.214520
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发表时间：
2000
影响因子：
3.7
通讯作者：
J. Malrieu
中科院分区：
文献类型：
--
作者：
C. Calzado;J. Malrieu
A series of accurate ab initio calculations on ${\mathrm{Cu}}_{p}{\mathrm{O}}_{q}$ finite clusters, properly embedded in the Madelung potential of the infinite lattice, have been performed in order to determine the local effective interactions in the ${\mathrm{CuO}}_{2}$ planes of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ compounds. The values of the first-neighbor interactions, magnetic coupling ${(J}_{\mathrm{NN}}=125$ meV), and hopping integral ${(t}_{\mathrm{NN}}=\ensuremath{-}555$ meV) have been confirmed. Important additional effects are evidenced, concerning essentially the second-neighbor hopping integral ${t}_{\mathrm{NNN}}=+110$ meV, the displacement of a singlet toward an adjacent colinear hole, ${h}_{\mathrm{SD}}^{\mathrm{abc}}=\ensuremath{-}80$ meV, a non-negligible hole-hole repulsion ${V}_{\mathrm{NN}}\ensuremath{-}{V}_{\mathrm{NNN}}=0.8$ eV, and a strong anisotropic effect of the presence of an adjacent hole on the values of the first-neighbor interactions. The dependence of ${J}_{\mathrm{NN}}$ and ${t}_{\mathrm{NN}}$ on the position of neighbor hole(s) has been rationalized from the two-band model and checked from a series of additional ab initio calculations. An extended $t\ensuremath{-}J$ model Hamiltonian has been proposed on the basis of these results. It is argued that the here-proposed three-body effects may play a role in the charge/spin separation observed in these compounds, that is, in the formation and dynamic of stripes.
A series of accurate ab initio calculations on ${\mathrm{Cu}}_{p}{\mathrm{O}}_{q}$ finite clusters, properly embedded in the Madelung potential of the infinite lattice, have been performed in order to determine the local effective interactions in the ${\mathrm{CuO}}_{2}$ planes of ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ compounds. The values of the first-neighbor interactions, magnetic coupling ${(J}_{\mathrm{NN}}=125$ meV), and hopping integral ${(t}_{\mathrm{NN}}=\ensuremath{-}555$ meV) have been confirmed. Important additional effects are evidenced, concerning essentially the second-neighbor hopping integral ${t}_{\mathrm{NNN}}=+110$ meV, the displacement of a singlet toward an adjacent colinear hole, ${h}_{\mathrm{SD}}^{\mathrm{abc}}=\ensuremath{-}80$ meV, a non-negligible hole-hole repulsion ${V}_{\mathrm{NN}}\ensuremath{-}{V}_{\mathrm{NNN}}=0.8$ eV, and a strong anisotropic effect of the presence of an adjacent hole on the values of the first-neighbor interactions. The dependence of ${J}_{\mathrm{NN}}$ and ${t}_{\mathrm{NN}}$ on the position of neighbor hole(s) has been rationalized from the two-band model and checked from a series of additional ab initio calculations. An extended $t\ensuremath{-}J$ model Hamiltonian has been proposed on the basis of these results. It is argued that the here-proposed three-body effects may play a role in the charge/spin separation observed in these compounds, that is, in the formation and dynamic of stripes.