A Hamiltonian for quantum copying

Abstract

We derive an explicit Hamiltonian for copying the basis up and down states of a quantum two-state system - a qubit - onto n "copy" qubits initially all prepared in the down state. In terms of spin components, for spin-1/2 particle spin states, the resulting Hamiltonian involves n- and (n+1)-spin interactions. The case n=1 also corresponds to a quantum-computing controlled-NOT gate.

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References in corpus (5)

• Elementary gates for quantum computation
• Measurement of conditional phase shifts for quantum logic
• Two-Bit Gates are Universal for Quantum Computation
• Maintaining coherence in Quantum Computers
• Quantum Computers, Factoring, and Decoherence

Cited by in corpus (4)

• Probabilistic cloning and identification of linearly independent quantum states
• Strategies and Networks for State-Dependent Quantum Cloning
• Probabilistic cloning with supplementary information
• Design of gates for quantum computation: the three-spin XOR gate in terms of two-spin interactions