Bound states and chiral excitation in the effective Floquet continuum within tilted waveguide lattices

This is the authors' abstract. We don't add key points for this paper.

We investigate the dynamics of light escaping from a tilted waveguide capable of supporting chiral light excitation into a two-band Su-Schrieffer-Heeger system functioning as a continuum. In a periodic scenario that gives rise to Floquet multibands, our research reveals that the effective bands, exhibiting time-reversal symmetry breaking, host bound states in the continuum (BICs) generated through coupling interference, alongside phenomena reminiscent of spontaneous radiation. Moreover, we analyze the influence of the zero mode on the BICs and the chiral transport of the excited Bloch waves within the tilt-induced Floquet bands. Our results establish a foundational pathway for exploring BICs in systems exhibiting time-reversal symmetry breaking.