2015/08/31 by Emily Davis, Gregory Bentsen, Monika Schleier-Smith · 3 citations
Physics and Astronomy · #quant-ph
paper · pdf · doi:10.1103/physrevlett.116.053601
published as Phys. Rev. Lett. 116, 053601 (2016) · 5 + 4 pages (main text + supplement), 4 figures; in press at PRL
arxiv created 2016/01/28 · arxiv updated 2016/02/03
We propose an approach to quantum phase estimation that can attain precision near the Heisenberg limit without requiring single-particle-resolved state detection. We show that the "one-axis twisting" interaction, well known for generating spin squeezing in atomic ensembles, can also amplify the output signal of an entanglement-enhanced interferometer to facilitate readout. Applying this interaction-based readout to oversqueezed, non-Gaussian states yields a Heisenberg scaling in phase sensitivity, which persists in the presence of detection noise as large as the quantum projection noise of an unentangled ensemble. Even in dissipative implementations -- e.g., employing light-mediated interactions in an optical cavity or Rydberg dressing -- the method significantly relaxes the detection resolution required for spectroscopy beyond the standard quantum limit.