Global Optical Control of a Quantum Spin Chain

Abstract

Quantum processors which combine the long decoherence times of spin qubits together with fast optical manipulation of excitons have recently been the subject of several proposals. I show here that arbitrary single- and entangling two-qubit gates can be performed in a chain of perpetually coupled spin qubits solely by using laser pulses to excite higher lying states. It is also demonstrated that universal quantum computing is possible even if these pulses are applied {\it globally} to a chain; by employing a repeating pattern of four distinct qubit units the need for individual qubit addressing is removed. Some current experimental qubit systems would lend themselves to implementing this idea.

5 pages, 3 figures

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Cited by in corpus (6)

• Entanglement distribution for a practical quantum-dot-based quantum processor architecture
• High fidelity all-optical control of quantum dot spins: detailed study of the adiabatic approach
• Global Control Methods for GHZ State Generation on 1-D Ising Chain
• All-Optical Measurement Based QIP in Quantum Dots
• An introduction to one-way quantum computing in distributed architectures
• Mesoporous matrices for quantum computation with improved response through redundance