报告题目：Spin Dynamics of Fermionic KRb Polar Molecules

报告人：林俊宇 博士

报告人单位：科罗拉多大学JILA

主持人：蒋燕义 研究员

报告时间：2026年8月4日（周二）上午10:00

报告地点：闵行校区光学大楼B225会议室

报告摘要：

Quantum gases of polar molecules have recently emerged as a powerful platform for exploring exotic many-body dynamics and correlated quantum behavior. In this talk, firstly, I will introduce our recent results of using KRb polar molecules for many-body Hamiltonian engineering [1-2]. Under full control of tunneling rate with different optical lattice depths and spin-spin interaction strength with DC electric fields, we systematically explored regimes of the t-J model inaccessible on other platforms. By applying microwave pulses for Floquet engineering, we showed the realization of the XYZ spin model with polar molecules. Secondly, I will introduce our recent progress on successfully evaporating fermionic KRb molecules in both 3D and 2D geometries to well below their Fermi temperatures [3]. This is for achieving low-entropy samples in different trapping geometries, to unlock the full potential of this platform. As the molecules are evaporated to deeper degeneracy, they enter the Pauli-blocked regime, limiting the final molecular temperature to about 25% of the Fermi temperature. This fundamental limit, set by the Pauli-exclusion principle, could be overcome in the future by using distinguishable scattering partners.

[1] Carroll, A. N. et al. Observation of generalized t-J spin dynamics with tunable dipolar interactions. Science 388, 381–386 (2025).

[2] Miller, C. et al. Two-axis twisting using Floquet-engineered XYZ spin models with polar molecules. Nature 633, 332–337 (2024).

[3] Lin, J. et al. Fermi gas of polar molecules in the Pauli-blocked regime. arXiv:2606.14135 (2026).

报告人简介：

林俊宇，现于科罗拉多大学JILA担任博士后。2022年于香港中文大学获得博士学位。主要从事超冷极性分子的实验研究。研究内容聚焦于分子间偶极相互作用的电场、微波调控，以及光晶格囚禁分子的多体量子系统的实现与操控。