In this paper, we demonstrate that the topological polaritonic states of a two-dimensional coupled matter-light system can be optically controlled. By introducing a squeezed light field, we generalized the model of topological polaritons, where the matter-light coupling constant winds in momentum space, leading to the nontrivial topology. The bulk excitation spectrum, polariton wave function, topological invariant, and edge mode spectrum are calculated. It is found that mixing the excitons with nonsqueezing photons will result in a time-reversalsymmetry- breaking quantum-spin-Hall-like polaritonic state. However, the quantum-Hall-like state arises when the photonic part of the polaritons is squeezed. Driven by the varying degree of squeezing, there is a topological phase transition with the closing of the bulk excitation gap. Across the phase transition, the direction of edge mode propagation is reversed, which is demonstrated by an edge mode simulation. Such a feature may provide an opportunity for realizing one-way edge channels with adjustable directionality. (C) 2016 Optical Society of America
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