Grand challenges for nanophotonics: Steering and riding light

Abstract

Research in nanophotonics is yielding advances towards grand challenges that have not previously been achievable. A first grand challenge is realization of comprehensively tunable metasurface nanoantenna arrays, which are enabling dynamic, active control of the constitutive properties of light - amplitude, phase, wavevector and polarization - opening new applications such as phased-array optical beam steering, visible light modulation for communication and thermal radiation management. I will discuss the concept of a 'universal' metasurface, i.e, one whose properties are arbitrarily reprogrammable, performing a wide array of functions, including lenses with reconfigurable focal lengths and beamsteering devices. A second grand challenge for nanophotonics is design of spacecraft capable of reaching the stars beyond our solar system, since light itself is the only fuel capable of propelling spacecraft to the relativistic speeds needed to achieve interstellar travel. I will show that this audacious concept may be closer than we imagine, if advances in nanophotonic materials can enable key concepts for spacecraft propulsion, and communications.