Correction to: Nature Photonics https://doi.org/10.1038/s41566-017-0006-2, published online 29 September 2017.

In the version of this Article originally published, equation (1) incorrectly read $$\hat H = \mathop {\sum}\limits_j {t\hat a_j\hat b_j^{\dagger} + t^\prime \hat a_j^{\dagger} \hat b_j + h.c.}$$; it should have read $$\hat H = \mathop {\sum}\limits_j {t\hat a_j\hat b_{j - 1}^{\dagger} + t^\prime \hat a_j^{\dagger} \hat b_j + h.c.}$$