Fig. 1. Schematic of the anisotropic programmable metasurface with individually controllable 2-bit elements for real-time and independent dual-polarized waves manipulation. By applying the different coding patterns onto the metasurface, it can generate different EM functions under orthogonal two polarized EM incidences, such as real-time beam scanning in the x-polarization channel and real-time beam generation in the y-polarization channel.

Fig. 2. Designed anisotropic programmable metasurface and its performance. (a) 3D view of the designed anisotropic programmable meta-element with two independent bias lines. Simulated (b) reflection amplitudes and (c) reflection phases of the anisotropic programmable meta-element with different capacitances Cx and Cy under the x- and y-polarized incidences. (d) Simulated reflection responses by changing the capacitances Cy of the meta-element under x-polarized incidences. (e) Front and back views of the fabricated anisotropic programmable metasurface with 420 individually controllable meta-elements. Measured (f) reflection phases and (g) reflection amplitudes of the metasurface sample under different biases ranging from 0 to 10.0 V.

Fig. 3. Real-time pencil beam scanning of the anisotropic programmable metasurface under x-polarized incidences. (a)–(d) Simulated 3D reflected beams pointing at −10°, −20°, −30°, and −40°, respectively, at 4.5 GHz under four different 2-bit coding patterns. (e), (f) Simulated 2D reflected beams of the anisotropic programmable metasurface at 4.0 and 5.0 GHz, respectively.

Fig. 4. Real-time vortex beam generation of the anisotropic programmable metasurface under y-polarized incidences. (a)–(f) Simulated amplitude distributions (left column) and phase distributions (right column) of the reflected electric-field for OAM mode l=±1 at 4.0, 4.5, and 5.0 GHz.

Fig. 5. Experimental verification of the anisotropic programmable metasurface. (a), (b) Far-field testing environment and measured reflected beams with different deflection angles of the sample under x-polarized incidence at 4.5 GHz. (c), (d) Near-field testing environment and measured amplitude and phase distributions of the reflected electric field for OAM mode l=±1 at 4.5 GHz.