Resonant optical phased arrays are a promising way
to reach fully reconfgurable metasurfaces in the optical and nearinfrared (NIR) regimes with low energy consumption, low
footprint, and high reliability. Continuously tunable resonant
structures suffer from inherent drawbacks such as low phase range,
amplitude-phase correlation, or extreme sensitivity that makes
precise control at the individual element level very challenging. We
computationally investigate 1-bit (binary) control as a mechanism
to bypass these issues. We consider a metasurface for beam steering
using a nanoresonator antenna and explore the theoretical
capabilities of such phased arrays. A thermally realistic structure
based on vanadium dioxide sandwiched in a metal−insulator−
metal structure is proposed and optimized using inverse design to
enhance its performance at 1550 nm. Continuous beam steering over 90° range is successfully achieved using binary control, with
excellent agreement with predictions based on the theoretical frst-principles description of phased arrays. Furthermore, a broadband
response from 1500 to 1700 nm is achieved. The robustness to the design manufacturing imperfections is also demonstrated. This
simplifed approach can be implemented to optimize tunable nanophotonic phased array metasurfaces based on other materials or
phased shifting mechanisms for various functionalities.