Spin and charge structures around vortices in underdoped high-temperature superconductorsGuo-Qiao Zha, Ling-Feng Zhang, Hao Meng, Hong-Wei Zhao and Shi-Ping Zhou
Department of Physics, Shanghai University - 99 Shangda Road, Shanghai 200444, PRC
received 16 July 2008; accepted in final form 25 August 2008; published October 2008
published online 19 September 2008
The effect of next-nearest-neighbor (nnn) hopping on the spin and charge structures around vortices in underdoped high-temperature superconductors is studied at finite temperature by numerically solving the Bogoliubov-de Gennes equations based on a model Hamiltonian with competing antiferromagnetic spin density wave (SDW) and d-wave superconductivity orders. We show that one-dimensional (1D) y- or x-axisoriented stripes for the SDW and the associated charge density wave (CDW) exist for small nnn hopping strengths. A coexistence of both y- and x-axisoriented stripes may occur for a relatively large nnn hopping strength. The two-dimensional (2D) spatial modulations with fourfold symmetry can be obtained with further enlarging nnn hopping strength, implying the possible existence of 2D checkerboard-like SDW and CDW orders. In addition, a transition of “1D stripe to 2D checkerboard-like pattern” can take place with increasing temperature.
74.20.-z - Theories and models of superconducting state.
74.25.Jb - Electronic structure.
74.25.Ha - Magnetic properties.
© EPLA 2008