Weak lasing in one-dimensional polariton superlattices.. L. Zhang, W. Xie, J. Wang, A. Poddubny, J. Lu, Y. Wang, J. Gu, W. Liu, D. Xu, X. Shen, Y. Rubo, B. Altshuler, A. V. Kavokin and Z. Chen in Proc. Natl. Acad. Sci. 112:E1516 (2015).