Optical magnetism and wavefront control by arrays of strontium atoms

By analyzing the parameters of electronic transitions, we show how bosonic Sr atoms in planar optical lattices can be engineered to exhibit magnetism and other higher-order electromagnetic multipoles that harnessed for wavefront control incident light. Resonant $\lambda\simeq 2.6\mu$m light $^3D_1\rightarrow {^3}P_0$ transition mediates cooperative interactions between while are trapped a deeply subwavelength lattice. The then collective excitation eigenmodes, e.g., with strong magnetic response at frequencies, despite individual having negligible coupling component We provide detailed scheme utilize excitations such modes consisting arrays form an atomic Huygens' surface, complete $2\pi$ phase transmitted almost no reflection, allowing nearly arbitrary shaping. In numerical examples, this is achieved by controlling level shifts off-resonant ${^3P}_J\rightarrow {^3D}_1$ which results simultaneous electric dipoles quadrupoles or dipoles. demonstrate engineering array realizing steering beam generation baby-Skyrmion texture via topologically nontrivial Gaussian Poincar\'{e} beam, contains all possible polarizations single cross-section.