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arXiv · 1709.07921

Spin order and phase transitions in chains of polariton condensates

H. Ohadi·A. J. Ramsay·H. Sigurdsson·Y. del Valle-Inclan Redondo·S. I. Tsintzos·Z. Hatzopoulos·T. C. H. Liew·I. A. Shelykh·Y. G. Rubo·P. G. Savvidis·J. J. Baumberg
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Abstract

We demonstrate that multiply-coupled spinor polariton condensates can be optically tuned through a sequence of spin-ordered phases by changing the coupling strength between nearest neighbors. For closed 4-condensate chains these phases span from ferromagnetic (FM) to antiferromagnetic (AFM), separated by an unexpected crossover phase. This crossover phase is composed of alternating FM-AFM bonds. For larger 8 condensate chains, we show the critical role of spatial inhomogeneities and demonstrate a scheme to overcome them and prepare any desired spin state. Our observations thus demonstrate a fully controllable non-equilibrium spin lattice.

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H. Ohadi, A. J. Ramsay, H. Sigurdsson, Y. del Valle-Inclan Redondo, S. I. Tsintzos, Z. Hatzopoulos, T. C. H. Liew, I. A. Shelykh, Y. G. Rubo, P. G. Savvidis, J. J. Baumberg. 2017-08-09. Spin order and phase transitions in chains of polariton condensates. https://doi.org/10.1103/physrevlett.119.067401

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