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Scalable register initialization for quantum computing in an optical lattice

Gavin K. Brennen·Guido Pupillo·Ana Maria Rey·Charles W. Clark·Carl J. Williams
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Abstract

The Mott insulator state created by loading an atomic Bose-Einstein condensate (BEC) into an optical lattice may be used as a means to prepare a register of atomic qubits in a quantum computer. Such architecture requires a lattice commensurately filled with atoms, which corresponds to the insulator state only in the limit of zero inter-well tunneling. We show that a lattice with spatial inhomogeneity created by a quadratic magnetic trapping potential can be used to isolate a subspace in the center which is impervious to hole-hoping. Components of the wavefunction with more than one atom in any well can be projected out by selective measurement on a molecular photo-associative transition. Maintaining the molecular coupling induces a quantum Zeno effect that can sustain a commensurately filled register for the duration of a quantum computation.

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Gavin K. Brennen, Guido Pupillo, Ana Maria Rey, Charles W. Clark, Carl J. Williams. 2003-12-08. Scalable register initialization for quantum computing in an optical lattice. https://doi.org/10.1088/0953-4075%2F38%2F11%2F010

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