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arXiv · 0801.1959

Quantum Information Processing with Quantum Zeno Many-Body Dynamics

Alex Monras·Oriol Romero-Isart
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Abstract

We show how the quantum Zeno effect can be exploited to control quantum many-body dynamics for quantum information and computation purposes. In particular, we consider a one dimensional array of three level systems interacting via a nearest-neighbour interaction. By encoding the qubit on two levels and using simple projective frequent measurements yielding the quantum Zeno effect, we demonstrate how to implement a well defined quantum register, quantum state transfer on demand, universal two-qubit gates and two-qubit parity measurements. Thus, we argue that the main ingredients for universal quantum computation can be achieved in a spin chain with an always-on and constant many-body Hamiltonian. We also show some possible modifications of the initially assumed dynamics in order to create maximally entangled qubit pairs and single qubit gates.

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Alex Monras, Oriol Romero-Isart. 2008-01-13. Quantum Information Processing with Quantum Zeno Many-Body Dynamics. https://arxiv.org/abs/0801.1959

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