Quantum information processing in a spin-bus system of coupled chains

Abstract

The effective Heisenberg interaction of long distance is constructed in spin qubits connected to a bus of two strongly coupled chains. Universal quantum computation can be realized on the basis of the bus which always keeps frozen at the ground state. It is found that the effective interaction is primarily determined by the energy spectra of the bus. With the variation of 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 the high precision are implemented in the condition of quantum fluctuations.

13 pages, 3 figures

References in corpus (7)

• Quantum state transmission via a spin ladder as a robust data bus
• Local Fault-tolerant Quantum Computation
• Efficient multiqubit entanglement via a spin-bus
• Quantum computing with a single molecular ensemble and a Cooper pair box
• A precise CNOT gate in the presence of large fabrication induced variations of the exchange interaction strength
• Analytic results on long distance entanglement mediated by gapped spin chains
• Quantum state transfer with untuneable couplings