Beam steering at the nanosecond time scale with an atomically thin reflector

Abstract

Techniques to mold the flow of light on subwavelength scales enable fundamentally new optical systems and device applications. The realization of programmable, active optical systems with fast, tunable components is among the outstanding challenges in the field. Here, we experimentally demonstrate a few-pixel beam steering device based on electrostatic gate control of excitons in an atomically thin semiconductor with strong light-matter interactions. By combining the high reflectivity of a MoSe2 monolayer with a graphene split-gate geometry, we shape the wavefront phase profile to achieve continuously tunable beam deflection with a range of 10${}^{\circ }$, two-dimensional beam steering, and switching times down to 1.6 nanoseconds. Our approach opens the door for a new class of atomically thin optical systems, such as rapidly switchable beam arrays and quantum metasurfaces operating at their fundamental thickness limit.

References in corpus (3)

• Cooperative resonances in light scattering from two-dimensional atomic arrays
• Atomically thin mirrors made of monolayer semiconductors
• Realization of an atomically thin mirror using monolayer MoSe2

Cited by in corpus (5)

• Characterizing superradiant dynamics in atomic arrays via a cumulant expansion approach
• Cooperative quantum-optical planar arrays of atoms
• Excitonic beam steering in an active van der Waals metasurface
• Optimized geometries for cooperative photon storage in an impurity coupled to a two-dimensional atomic array
• Photonics in Flatland: Challenges and Opportunities for Nanophotonics with 2D Semiconductors