The generating and modulating characteristics of bound states in the continuum for both TE and TM polarizations by one-dimensional photonic crystal slabs

Abstract

Optical bound states in the continuum (BICs) are capable of manipulating the polarization, confinement, and coupling of light with infinitely high-quality factor. The emerging design based on photonic crystal (PhC) slabs has led to the realization of novel platforms with strong light–matter interaction, but these structures usually are sensitive to the polarization of light. Here, we report theoretically that both transverse-electric (TE) and transverse-magnetic (TM) polarized BICs at telecommunication wavelengths can be simultaneously constructed based on one-dimensional dielectric PhC slabs. By means of the mode expansion method, the essential characteristics of these BICs are systematically investigated in this structure, including the formation and modulation of the symmetry-protected and non-symmetry-protected BICs for different polarizations. It is derived that these BICs can be achieved independent of the incident polarization and for a broad range of propagating constants. These results can provide potential applications for efficient biosensing and perfectly filtering as well as to study various nonlinear phenomena.