Center for Quantum Phenomena Seminars

A central goal of Quantum Information Science (QIS) is to harness entanglement for practical advantage. While much of the public attention on QIS has focused on quantum computing, the quantum metrology community has made tremendous progress in developing strategies and platforms for surpassing classical limits on measurement precision. Spin squeezing has emerged as one of the most promising routes to quantum-enhanced precision in atomic clocks, magnetometers, and inertial sensors. While spin squeezing has been extensively studied for infinite-range and homogeneous interactions, recent experimental realizations in finite-range platforms such as trapped ions and Rydberg arrays have opened the door to scalable squeezing by exploiting the spatiotemporal control, significantly broadening the scope of experimentally accessible platforms. In this talk, I will present my work on entanglement generation in bilayers of power-law interacting spin models, where spatiotemporal control of the interactions enables significant improvements in sensitivity scaling over conventional approaches. I will first show how Floquet-engineered spatially anisotropic interactions can improve the metrological scaling from the standard quantum limit (1/√N) to the ultimate Heisenberg limit (1/N). I will then demonstrate that the squeezing dynamics hosts a dynamical phase transition between a fully collective phase with Heisenberg-limited squeezing and a partially collective phase with scalable squeezing. This transition is explained within the framework of nonequilibrium critical phenomena through universal scaling of the full-time dynamics. Finally, I will discuss ongoing work examining the robustness and scope of this universality, including the role of lattice geometry, dimensionality, and interaction engineering in shaping the phase diagram and the critical scaling. These results are relevant to current experiments with Rydberg arrays, polar molecules, and trapped ions, and point toward broader connections between entanglement generation and nonequilibrium universality classes.