报告人：胡时杰 特聘研究员（北京计算科学研究中心）

题目：Spinon Singlet: Origin of d-Wave Pairing in a Partially-Filled Stripe

时间：2026年7月12日（周日）下午15：00

地点：理工楼1226

联系人：赵继泽

报告摘要：

Significant research advances have led to a consensus that the Fermi-Hubbard model and its extended variants are archetypal frameworks for elucidating the intertwined relationship between stripe orders and superconductivity in hole-doped high-Tc materials. Notably, the Hubbard quantum simulator has recently achieved several remarkable breakthroughs, e.g., being successfully cooled down to the cryogenic regime and enabling the observation of stable fluctuating stripes. However, the microscopic mechanism behind d-wave pairing of electrons in the presence of stripes at low temperatures remains poorly understood due to the intricate interplay among the strongly correlated effects and non-negligible thermal fluctuations. Here, we conduct a close investigation of a partially-filled stripe in the representative t-J and t-t'-U models with both numerical and analytical methods. Analogous to quantum gas microscopy, the perfect sampling technique allows us to obtain the high-confidence statistics of the Fock basis states appearing in the ground-state wavefunction. In a refreshing physical paradigm, these data demonstrate that two spinons with opposite chiralities tend to spontaneously pair into a singlet state, which naturally gives rise to the d-wave pairing pattern. Then, using the effective theory of quantum colored string, we reconstruct the wavefunction and determine the nature of spinon pairing and its connection to the d-wave pairing pattern. Furthermore, spinon singlet pairs enable the establishment of a long-range pair-pair correlation between double stripes. Our work offers new insights into the role of stripe orders in mediating $d$-wave superconductivity and paves the way for further exploration of multi-stripe-mediated pairing mechanisms in the Fermi-Hubbard model.

个人简介：

胡时杰，2010年于中国科学院理论物理研究所获得博士学位。先后在德国哥廷根大学、马克斯普朗克复杂系统物理研究所、凯撒斯劳滕工业大学从事博士后工作。现任北京计算科学研究中心特聘研究员、博士生导师。研究方向聚焦于量子多体计算方法与技术的发展，以及面向强关联系统的高效计算软件库开发；同时开展量子磁性、超冷原子、非常规超导等方向的数值计算与理论研究工作。迄今，发表学术论文30余篇，包括7篇Phys.Rev.Lett，2 篇Nature Commun.。2021年获中组部青年千人计划资助。