Enhanced cooperativity for quantum-nondemolition-measurement–induced spin squeezing of atoms coupled to a nanophotonic waveguide

2017/12/31 by Xiaodong Qi, Yuan-Yu Jau, Yuan‐Yu Jau +2 · 9 citations
Chemistry · Computer Science · Physics and Astronomy · #Atom (system on chip) #Atomic physics #Chemistry #Cooperativity #Mechanical and Optical Resonators #Nanophotonics #Optics #Physics #Quantum #Quantum Information and Cryptography #Quantum decoherence #Quantum mechanics #Quantum optics and atomic interactions #Waveguide #physics.atom-ph #physics.optics #quant-ph

paper · pdf · doi:10.1103/physreva.97.033829

published in Physical Review A 97(3) (American Physical Society) · 8 pages + 2 pages appendix with 7 figures. To appear on Phys. Rev. A

openalex created_date 2017/12/22 · arxiv created 2018/03/15 · openalex publication_date 2018/03/16 · arxiv updated 2018/03/21 · openalex updated_date 2026/08/06

Abstract

We study the enhancement of cooperativity in the atom-light interface near a nanophotonic waveguide for application to quantum nondemolition (QND) measurement of atomic spins. Here the cooperativity per atom is determined by the ratio between the measurement strength and the decoherence rate. Counterintuitively, we find that by placing the atoms at an azimuthal position where the guided probe mode has the lowest intensity, we increase the cooperativity. This arises because the QND measurement strength depends on the interference between the probe and scattered light guided into an orthogonal polarization mode, while the decoherence rate depends on the local intensity of the probe. Thus, by proper choice of geometry, the ratio of good-to-bad scattering can be strongly enhanced for highly anisotropic modes. We apply this to study spin squeezing resulting from QND measurement of spin projection noise via the Faraday effect in two nanophotonic geometries, a cylindrical nanofiber and a square waveguide. We find that, with about 2500 atoms and using realistic experimental parameters, \ensuremath∼6.3 and \ensuremath∼13 dB of squeezing can be achieved on the nanofiber and square waveguide, respectively.

Citations

• A straightforward introduction to continuous quantum measurement
• Storage of fiber-guided light in a nanofiber-trapped ensemble of cold atoms
• Spin squeezing and reduced quantum noise in spectroscopy
• Spin Squeezing of a Cold Atomic Ensemble with the Nuclear Spin of One-Half
• Quantum computing by optical control of electron spins
• Trapped atoms in cavity QED: coupling quantized light and matter
• Manipulating quantum entanglement with atoms and photons in a cavity
• Optical Interface Created by Laser-Cooled Atoms Trapped in the Evanescent Field Surrounding an Optical Nanofiber
• States of an Ensemble of Two-Level Atoms with Reduced Quantum Uncertainty
• Dispersive Optical Interface Based on Nanofiber-Trapped Atoms
• Spin squeezing of atomic ensembles by multicolor quantum nondemolition measurements
• Strong coupling of a single photon to a superconducting qubit using circuit quantum electrodynamics
• Dynamics of trapped atoms around an optical nanofiber probed through polarimetry
• Super-radiance reveals infinite-range dipole interactions through a nanofiber