Single-peak-regulation and wide-angle dual-band metamaterial absorber based on hollow-cross and solid-cross resonatorsYibo Tang, Longhui He, Jianming Xu, Hailang He, Yuhan Li and Anfeng LiuEur. Phys. J. Appl. Phys., 91 3 (2020) 30901DOI: https://doi.org/10.1051/epjap/2020200145