Georgakilas Ioannis, Tiede David, Urbonas Darius, Mirek Rafał, Bujalance Clara, Caliò Laura, Oddi Virginia, Tao Rui, Dirin Dmitry N, Rainò Gabriele, Boehme Simon C, Galisteo-López Juan F, Mahrt Rainer F, Kovalenko Maksym V, Miguez Hernán, Stöferle Thilo
IBM Research Europe - Zurich, Säumerstrasse 4, 8803, Rüschlikon, Switzerland.
Institute of Quantum Electronics, Department of Physics, ETH Zürich, Auguste-Piccard-Hof 1, 8093, Zürich, Switzerland.
Nat Commun. 2025 Jun 5;16(1):5228. doi: 10.1038/s41467-025-60553-3.
The exploitation of the strong light-matter coupling regime and exciton-polariton condensates has emerged as a compelling approach to introduce strong interactions and nonlinearities into numerous photonic applications. The use of colloidal semiconductor quantum dots with strong three-dimensional confinement as the active material in optical microcavities would be highly advantageous due to their versatile structural and compositional tunability and wet-chemical processability, as well as potentially enhanced, confinement-induced polaritonic interactions. Yet, to date, exciton-polariton condensation in a microcavity has neither been achieved with epitaxial nor with colloidal quantum dots. Here, we demonstrate room-temperature polariton condensation in a thin film of monodisperse, colloidal CsPbBr quantum dots, placed in a tunable optical resonator with a Gaussian-shaped deformation serving as wavelength-scale potential well for polaritons. The onset of polariton condensation under pulsed optical excitation is manifested in emission by its characteristic superlinear intensity dependence, reduced linewidth, blueshift, and extended temporal coherence.
利用强光与物质耦合机制和激子极化激元凝聚,已成为一种引人注目的方法,可将强相互作用和非线性引入众多光子应用中。使用具有强三维限制的胶体半导体量子点作为光学微腔中的活性材料将非常有利,这是由于其具有多样的结构和成分可调性以及湿化学可加工性,还有可能增强的、由限制诱导的极化激元相互作用。然而,迄今为止,无论是外延量子点还是胶体量子点,都尚未在微腔中实现激子极化激元凝聚。在此,我们展示了在单分散胶体CsPbBr量子点薄膜中的室温极化激元凝聚,该薄膜置于一个可调谐光学谐振器中,该谐振器具有高斯形状的形变,作为极化激元的波长尺度势阱。在脉冲光激发下极化激元凝聚的起始表现为发射光具有特征性的超线性强度依赖性、减小的线宽、蓝移和延长的时间相干性。