Voltage-controlled beam steering in liquid-crystal-integrated dual-mode plasmonic nanolaser

TL;DR

This paper demonstrates a voltage-controlled liquid crystal integrated plasmonic nanolaser capable of active, reversible beam steering at near-infrared wavelengths, with potential applications in reconfigurable nanophotonic devices.

Contribution

It introduces a novel liquid crystal-integrated plasmonic nanolaser design that achieves active beam steering and dual-mode operation without changing the cavity structure.

Findings

Achieved up to ±67° beam deflection with less than 1° divergence.

Supported dual lasing wavelengths with independent voltage tuning.

Maintained stable emission while actively steering the beam.

Abstract

Dynamic control of laser emission direction is crucial for developing compact and reconfigurable nanophotonic devices. In this work, we numerically present a plasmonic nanolaser (PNL) integrated with a voltage-controlled liquid crystal (LC) layer to achieve active beam steering. We modeled the orientation of LC molecules under an applied bias and incorporated this into electromagnetic simulations to assess the optical response. We observed lasing at an emission wavelength of 870 nm for the single-mode PNL, with discrete voltage-dependent deflections of the far-field emission of up to $\pm67$\textdegree, while maintaining a beam divergence of less than 1\textdegree. The steering characteristics were significantly influenced by the electro-optic properties of the LC layer, with an optimized thickness of 3 $\mu$m. The structural periodicity governed the achievable angular separation and emission stability. Furthermore, we extended the concept to a dual-mode nanolaser based on a merged nanohole array (NHA), which supports two lasing wavelengths at 873 nm and 880 nm. Both lasing modes exhibited simultaneous voltage-dependent angular tuning without altering the cavity geometry. These results highlight the potential of LC-integrated PNLs as voltage-controlled, reconfigurable light sources for applications in optical interconnects, beam routing, adaptive imaging, and multiplexed communication.