Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2208.01869

Enhancing spin squeezing using soft-core interactions

Jeremy T. Young, Sean R. Muleady, Michael A. Perlin, Adam M. Kaufman, Ana María Rey

Published Aug 3, 2022• 0 citations
arXivHTMLPDF

Abstract

We propose a new protocol for preparing spin squeezed states in controllable atomic, molecular, and optical systems, with particular relevance to emerging optical clock platforms compatible with Rydberg interactions. By combining a short-ranged, soft-core potential with an external drive, we can transform naturally emerging Ising interactions into an XX spin model while opening a many-body gap. The gap helps maintain the system within a collective manifold of states where metrologically useful spin squeezing can be generated at a level comparable to the spin squeezing generated in systems with genuine all-to-all interactions. We examine the robustness of our protocol to experimentally-relevant decoherence and show favorable performance over typical protocols lacking gap protection.

DOI
10.48550/arxiv.2208.01869

Related papers

Enhancing spin squeezing using soft-core interactions

Jeremy T. Young, Sean R. Muleady, Michael A. Perlin +2 more

Ising interactions in the form of a soft-core potential, such as the ones experienced by Rydberg dressed atoms, can be combined with a strong coherent drive to help preserve collective spin coherences even in systems much larger than the range of the soft-core interactions. As a result, they can lead to the robust generation of metrologically useful spin-squeezed states in optical tweezer clocks.

Physical Review Research•Mar 10, 2023•18 citations

Enhanced and Long-Lived Spin Squeezing in 2D Finite-Range Systems via Global Control Fields

Anonymous, Zhen-Xing Hua, Meng Khoon Tey +2 more

Spin squeezing is both a fundamental witness of quantum entanglement and a key resource for quantum-enhanced metrology. While all-to-all interactions provide a paradigmatic route to generate spin squeezing, many programmable quantum simulators naturally realize finite-range interactions that induce coupling between collective spin dynamics and finite-momentum spin-wave modes, thereby degrading the achievable squeezing. Here we develop an optimization-based global-control strategy for enhancing spin squeezing in a two-dimensional XX model with dipolar interactions. By combining rotor-spin-wave theory with an extension to open boundary conditions, we enable efficient optimization of control protocols for large finite-range interacting systems. We show that a single collective transverse field generates squeezing beyond the conventional two-axis-twisting benchmark across system sizes accessible to numerical benchmarking. The optimized dynamics exploits squeezing-axis reorientation while suppressing spin-wave excitations, thereby stabilizing strong squeezing over extended times. We further implement the optimized protocol in a two-dimensional Rydberg-atom array and experimentally observe enhanced, long-lived spin squeezing in good agreement with theory.

Physical Review Letters•Sep 9, 2026•0 citations

Spin Squeezing with Itinerant Magnetic Dipoles

Alec Douglas, Vassilios Kaxiras, Lin Su +4 more

Entanglement can improve the measurement precision of quantum sensors beyond the shot noise limit. Neutral atoms, the basis of some of the most precise and accurate optical clocks and interferometers, do not naturally exhibit the all-to-all interactions traditionally used to generate such entangled states. On the other hand, these systems exhibit exceedingly high degrees of experimental control over parameters such as temperature, spatial entropy, and itinerancy. In this work, we investigate spin squeezing in a highly coherent itinerant system of neutral atoms with magnetic dipole-dipole interactions. We achieve 7.1 dB of metrologically useful squeezing using finite-range spin-exchange interactions in an erbium quantum gas microscope, and we demonstrate that introducing atomic motion, realizing a dipolar t − J model, protects the spin sector coherence at low fillings, significantly improving the achievable spin squeezing in a 2D dipolar system. This work’s protocol can be implemented with most neutral atoms, opening the door to quantum-enhanced metrology in other itinerant dipolar systems, such as molecules or optical lattice clocks, and serves as a novel method for studying itinerant quantum magnetism with long-range interactions.

arXiv:2411.07219•Physical Review X•Aug 15, 2025•3 citations

Noise-resistant optimal spin squeezing via quantum control

T. Pichler, Tommaso Caneva, Simone Montangero +2 more

Entangled atomic states, such as spin-squeezed states, represent a promising resource for a new generation of quantum sensors and atomic clocks. We demonstrate that optimal control techniques can be used to substantially enhance the degree of spin squeezing in strongly interacting many-body systems, even in the presence of noise and imperfections. Specifically, we present a protocol that is robust to noise and outperforms conventional methods. Potential experimental implementations are discussed.

arXiv:1304.7195•Physical Review A•Jan 27, 2016•34 citations

Gap-Protected Heisenberg-Limited Squeezing with Locally Interacting Multi-Level Spins

Sakshi Bahamnia, Sagar Chaudhary, Arman Duha +1 more

We demonstrate a general mechanism to generate scalable, metrologically useful entanglement in the form of generalized spin squeezing in multi-level (qudit) spin systems with power-law interactions. We demonstrate this for spin-changing dynamics, extending the physics of spin-nematic squeezing known from spinor BECs to spatially extended lattice geometries. In the absence of all-to-all connectivity, the dynamics generally suffers from leakage into non-collective finite-momentum modes, destroying Heisenberg scaling. We show that introducing local $\mathfrak{su}(D)$ exchange interactions establishes an energy gap that protects the fully symmetric collective manifold, suppressing non-collective excitations, and achieving Heisenberg scaling $ξ^2\propto1/N$ in one to three dimensions for any power-law exponent. We provide an analytical understanding of the mechanism via the analysis of the Bogoliubov excitation spectrum, and demonstrate its effectiveness via numerical simulations of the quantum many-body dynamics. Our findings more broadly apply to other spin-squeezing Hamiltonians, and directly generalize to larger internal spin dimensions. Our results provide a practical pathway towards scalable Heisenberg-limited qudit entanglement generation in experimental platforms such as arrays of (polar) molecules, magnetic atoms, and Rydberg atoms realizing multi-level spin systems.

quant-pharXiv:2610.02314•Oct 5, 2026•0 citations

Spin Squeezing with Short-Range Spin-Exchange Interactions

Michael A. Perlin, Chunlei Qu, Ana María Rey

We investigate many-body spin squeezing dynamics in an XXZ model with interactions that fall off with distance r as 1/r^{α} in D=2 and 3 spatial dimensions. In stark contrast to the Ising model, we find a broad parameter regime where spin squeezing comparable to the infinite-range α=0 limit is achievable even when interactions are short ranged, α>D. A region of "collective" behavior in which optimal squeezing grows with system size extends all the way to the α→∞ limit of nearest-neighbor interactions. Our predictions, made using the discrete truncated Wigner approximation, are testable in a variety of experimental cold atomic, molecular, and optical platforms.

arXiv:2006.00723•Physical Review Letters•Nov 24, 2020•82 citations
We propose a new protocol for preparing spin squeezed states in controllable atomic, molecular, and optical systems, with particular relevance to emerging optical clock platforms compatible with Rydberg interactions. By combining a short-ranged, soft-core potential with an external drive, we can transform naturally emerging Ising interactions into an XX spin model while opening a many-body gap. The gap helps maintain the system within a collective manifold of states where metrologically useful spin squeezing can be generated at a level comparable to the spin squeezing generated in systems with genuine all-to-all interactions. We examine the robustness of our protocol to experimentally-relevant decoherence and show favorable performance over typical protocols lacking gap protection.
Spin squeezing is both a fundamental witness of quantum entanglement and a key resource for quantum-enhanced metrology. While all-to-all interactions provide a paradigmatic route to generate spin squeezing, many programmable quantum simulators naturally realize finite-range interactions that induce coupling between collective spin dynamics and finite-momentum spin-wave modes, thereby degrading the achievable squeezing. Here we develop an optimization-based global-control strategy for enhancing spin squeezing in a two-dimensional XX model with dipolar interactions. By combining rotor-spin-wave theory with an extension to open boundary conditions, we enable efficient optimization of control protocols for large finite-range interacting systems. We show that a single collective transverse field generates squeezing beyond the conventional two-axis-twisting benchmark across system sizes accessible to numerical benchmarking. The optimized dynamics exploits squeezing-axis reorientation while suppressing spin-wave excitations, thereby stabilizing strong squeezing over extended times. We further implement the optimized protocol in a two-dimensional Rydberg-atom array and experimentally observe enhanced, long-lived spin squeezing in good agreement with theory.
Entanglement can improve the measurement precision of quantum sensors beyond the shot noise limit. Neutral atoms, the basis of some of the most precise and accurate optical clocks and interferometers, do not naturally exhibit the all-to-all interactions traditionally used to generate such entangled states. On the other hand, these systems exhibit exceedingly high degrees of experimental control over parameters such as temperature, spatial entropy, and itinerancy. In this work, we investigate spin squeezing in a highly coherent itinerant system of neutral atoms with magnetic dipole-dipole interactions. We achieve 7.1 dB of metrologically useful squeezing using finite-range spin-exchange interactions in an erbium quantum gas microscope, and we demonstrate that introducing atomic motion, realizing a dipolar t − J model, protects the spin sector coherence at low fillings, significantly improving the achievable spin squeezing in a 2D dipolar system. This work’s protocol can be implemented with most neutral atoms, opening the door to quantum-enhanced metrology in other itinerant dipolar systems, such as molecules or optical lattice clocks, and serves as a novel method for studying itinerant quantum magnetism with long-range interactions.
Entangled atomic states, such as spin-squeezed states, represent a promising resource for a new generation of quantum sensors and atomic clocks. We demonstrate that optimal control techniques can be used to substantially enhance the degree of spin squeezing in strongly interacting many-body systems, even in the presence of noise and imperfections. Specifically, we present a protocol that is robust to noise and outperforms conventional methods. Potential experimental implementations are discussed.
We demonstrate a general mechanism to generate scalable, metrologically useful entanglement in the form of generalized spin squeezing in multi-level (qudit) spin systems with power-law interactions. We demonstrate this for spin-changing dynamics, extending the physics of spin-nematic squeezing known from spinor BECs to spatially extended lattice geometries. In the absence of all-to-all connectivity, the dynamics generally suffers from leakage into non-collective finite-momentum modes, destroying Heisenberg scaling. We show that introducing local su(D)\mathfrak{su}(D)su(D) exchange interactions establishes an energy gap that protects the fully symmetric collective manifold, suppressing non-collective excitations, and achieving Heisenberg scaling ξ2∝1/Nξ^2\propto1/Nξ2∝1/N in one to three dimensions for any power-law exponent. We provide an analytical understanding of the mechanism via the analysis of the Bogoliubov excitation spectrum, and demonstrate its effectiveness via numerical simulations of the quantum many-body dynamics. Our findings more broadly apply to other spin-squeezing Hamiltonians, and directly generalize to larger internal spin dimensions. Our results provide a practical pathway towards scalable Heisenberg-limited qudit entanglement generation in experimental platforms such as arrays of (polar) molecules, magnetic atoms, and Rydberg atoms realizing multi-level spin systems.
We investigate many-body spin squeezing dynamics in an XXZ model with interactions that fall off with distance r as 1/r^{α} in D=2 and 3 spatial dimensions. In stark contrast to the Ising model, we find a broad parameter regime where spin squeezing comparable to the infinite-range α=0 limit is achievable even when interactions are short ranged, α>D. A region of "collective" behavior in which optimal squeezing grows with system size extends all the way to the α→∞ limit of nearest-neighbor interactions. Our predictions, made using the discrete truncated Wigner approximation, are testable in a variety of experimental cold atomic, molecular, and optical platforms.