报告题目： Stimulated cooling in non-equilibrium Bose–Einstein condensate
报告人： Prof. Anton V. Zasedatelev（Aalto University, Finland）
报告人单位：芬兰阿尔托大学（Aalto University, Finland）
主持人：孙政研究员
报告时间：2026年7月22日（周三）上午10:00-12:00
报告地点：闵行校区光学大楼 B325会议室
报告摘要：
Bose–Einstein condensation is a striking manifestation of collective quantum behaviour on a macroscopic scale. In light–matter systems, the combination of strong interactions and extremely small effective mass enables condensation far from thermal equilibrium [1]. This raises a central question: how are temperature and coherence established in a driven–dissipative Bose gas? - I will present our recent work on experimental observation of stimulated cooling in the non-equilibrium Bose-Einstein condensate (BEC) of weakly interacting exciton-polaritons from room temperature down to 16K [2]. Our results indicate that the temperature of the weakly interacting Bose gas is universally set by the density-dependent chemical potential, revealing a defining property of non-equilibrium BECs [3]. We demonstrate that the stimulated nature of the cooling process directly governs the emergence of quantum coherence of the condensate and shapes the dissipative properties of the excited states.
References
[1] J. Kasprzak, M. Richard, S. Kundermann, A. Baas, P. Jeambrun, J. M. J. Keeling, F. M. Marchetti, M. H. Szymańska, R. André, J. L. Staehli, V. Savona, P. B. Littlewood, B. Deveaud, and L. S. Dang, “Bose–Einstein condensation of exciton polaritons,” Nature 443, 409–414 (2006).
[2] K. K. K. Ho, V. Yu. Shishkov, M. Amini, L. T. Wrathall, E. Mamonov, D. Urbonas, I. Georgakilas, T. Herkenrath, M. Forster, U. Scherf, T. Niemi, P. Törmä, and A. V. Zasedatelev, “Stimulated cooling in non-equilibrium Bose–Einstein condensate,” arXiv preprint arXiv:2601.15080 (2026).
[3] V. Yu. Shishkov, E. S. Andrianov, A. V. Zasedatelev, P. G. Lagoudakis, and Yu. E. Lozovik, “Exact analytical solution for the density matrix of a nonequilibrium polariton Bose–Einstein condensate,” Physical Review Letters 128, 065301 (2022).
报告人简介：
Anton Zasedatelev 在莫斯科获得博士学位，随后前往英国南安普顿大学开展博士后研究，主要研究光–物质玻色–爱因斯坦凝聚体（Bose–Einstein condensates, BEC）中的量子关联；之后又赴奥地利维也纳从事博士后研究，研究光学俘获粒子的量子运动。2025 年，他加入芬兰阿尔托大学（Aalto University），创建并领导宏观量子光学（Macroscopic Quantum Optics, MQO）研究团队。该团队的研究方向主要包括：固态和分子体系中的光与物质量子关联、非平衡光–物质玻色–爱因斯坦凝聚（BEC），以及大质量物体运动的量子调控。