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arXiv · 1608.08221

Robust symmetry-protected metrology with the Haldane phase

Stephen D. Bartlett·Gavin K. Brennen·Akimasa Miyake
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Abstract

We propose a metrology scheme that is made robust to a wide range of noise processes by using the passive, error-preventing properties of symmetry-protected topological phases. The so-called fractionalized edge mode of an antiferromagnetic Heisenberg spin-1 chain in a rotationally-symmetric Haldane phase can be used to measure the direction of an unknown electric field, by exploiting the way in which the field direction reduces the symmetry of the chain. Specifically, the direction of the field is registered in the holonomy under an adiabatic sensing protocol, and the degenerate fractionalized edge mode is protected through this process by the remaining reduced symmetry. We illustrate the scheme with respect to a potential realization by Rydberg dressed atoms.

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Stephen D. Bartlett, Gavin K. Brennen, Akimasa Miyake. 2017-11-22. Robust symmetry-protected metrology with the Haldane phase. https://doi.org/10.1088/2058-9565%2Faa9c56

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