Superradiance of a 2D-spaser array

TL;DR

This paper shows that a 2D array of interacting spasers can synchronize and produce superradiant emission, with power scaling quadratically with the number of spasers for small arrays and highly directional beams for larger arrays.

Contribution

It introduces the concept of mutual synchronization in 2D spaser arrays leading to superradiance, a novel way to generate efficient far-field radiation.

Findings

Total radiated power scales as N^2 for small arrays.

Radiation becomes highly directional for larger arrays.

Array arrangement enhances far-field emission efficiency.

Abstract

We demonstrate that interacting spasers arranged in a 2D array of arbitrary size can be mutually synchronized allowing them to supperradiate. For arrays smaller than the free space wavelength, the total radiated power is proportional to the square of the number N of spasers. For larger arrays, the radiation power is linear in N. However, the emitted beam becomes highly directional with intensity of radiation proportional to N^2 in the direction perpendicular to the plane of the array. Thus, spasers, which mainly amplify near fields, become an efficient source of far field radiation when they are arranged into an array.