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arXiv · 0912.1075

Entangling the lattice clock: Towards Heisenberg-limited timekeeping

Jonathan D. Weinstein·Kyle Beloy·Andrei Derevianko
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Abstract

We present a scheme for entangling the atoms of an optical lattice to reduce the quantum projection noise of a clock measurement. The divalent clock atoms are held in a lattice at a ``magic'' wavelength that does not perturb the clock frequency -- to maintain clock accuracy -- while an open-shell J=1/2 ``head'' atom is coherently transported between lattice sites via the lattice polarization. This polarization-dependent ``Archimedes' screw'' transport at magic wavelength takes advantage of the vanishing vector polarizability of the scalar, J=0, clock states of bosonic isotopes of divalent atoms. The on-site interactions between the clock atoms and the head atom are used to engineer entanglement and for clock readout.

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Jonathan D. Weinstein, Kyle Beloy, Andrei Derevianko. 2009-12-06. Entangling the lattice clock: Towards Heisenberg-limited timekeeping. https://doi.org/10.1103/physreva.81.030302

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