Effects of the Linear Polarization of Polariton Condensates in Their Propagation in Codirectional Couplers

We report on the linear polarization of polariton condensates in a codirectional coupler that allows evanescent coupling between adjacent waveguides. During the condensate's formation, polaritons usually acquire a randomly oriented polarization, however, our results reveal a preferential orientation of the linear polarization along the waveguide propagation path. Furthermore, we observe polarization-dependent intensity oscillations in the output terminal of the coupler, and we identify the mode beating between the linear-polarized eigenmodes as the origin of these oscillations. Our findings provide an insight into the control of the polarization of polariton condensates, paving the way for the development of spin-based polaritonic architectures where condensates propagate over macroscopic distances
This work has been partly supported by the Spanish MINECO Grant Nos. MAT2017-83722-R and PID2020-113445GB-I00. A.Y. and I.A.S. were financially supported by the Ministry of Science and Higher Education of the Russian Federation through Megagrant Number 14.Y26.31.0015 and Goszadanie No. 2019-1246. I.A.S. acknowledges also the support from theIcelandic research fund, Grant No. 163082-051. The Würzburgand Jena group acknowledges financial support within the DFGProject Nos. PE 523/18-1 and KL3124/2-1. The Würzburggroup acknowledges financial support by the German ResearchFoundation (DFG) under Germany’s Excellence Strategy−EXC2147 “ct.qmat” (Project No. 390858490) and is grateful forsupport by the state of Bavaria