Optimal quantum chain communication by end gates

Abstract

The scalability of solid state quantum computation relies on the ability of connecting the qubits to the macroscopic world. Quantum chains can be used as quantum wires to keep regions of external control at a distance. However even in the absence of external noise their transfer fidelity is too low to assure reliable connections. We propose a method of optimizing the fidelity by minimal usage of the available resources, consisting of applying a suitable sequence of two-qubit gates at the end of the chain. Our scheme allows also the preparation of states in the first excitation sector as well as cooling.

6 pages, 4 figures; improved version includes discussion on finitely many gate applications

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Cited by in corpus (6)

• Local controllability of quantum networks
• Fast, high fidelity information transmission through spin chain quantum wires
• Iterative quantum state transfer along a chain of nuclear spin qubits
• Quantum Data Bus in Dipolar Coupled Nuclear Spin Qubits
• Heisenberg chains cannot mirror a state
• High fidelity state transfer in binary tree spin networks