耦合链自旋总线中的量子信息处理

he effective Heisenberg interaction of long distance is evaluated in spin qubits that are connected to a bus of two strongly coupled chains. Universal quantum computation can be realized in the bus that is kept frozen at the ground state. The effective interaction is primarily determined by the energy spectra of the bus. By varying the distance between two connecting nodes, the interaction alternately occurs between antiferromagnetic and ferromagnetic ones. The long range interaction can also be attained in coupled infinite chains. The quantum gate operations with high precision can be realized even when the fluctuations are included in the system.