ZIM Laser: Zero-Index-Materials Laser

Abstract

We present a novel type of erbium-doped silicon onchip 1550-nm C-band laser based on the three-dimensional (3-D) zero-index material or ZIM laser. The underlying lasing physics of the ZIM laser is the bound state in continuum or BiC of individual erbium-doped silicon pillar element for gain achievement and zero refractive indexes for interelement phase coherence achievement. The BiC is the mixing of a monopole mode, a dipole mode, and a longitudinal mode, greatly reducing the radiation loss. Through careful multiphysics ZIM laser design, the 2-D erbium-doped silicon array can be tuned to near-zero permeability and permeability at a specific lasing wavelength to achieve interelement phase coherence. Such phase coherence mechanism of the ZIM laser differs significantly from the cavity-based lasers, such as the Fabry-Perot cavity laser. Because only a specifically designed wavelength can achieve near-zero permeability and permeability, the ZIM laser only works at single mode and multimodes competition disappears. So, the length of the ZIM laser can be arbitrary long to achieve the desired power, without the need of a filter at the lasing mode to remove unnecessary lasing modes. In this paper, we have designed and simulate the ZIM laser at the 1550-nm C-band. We obtained the BiC field pattern, its radiation Q factor, transmission/reflection, effective refractive index, and dispersion property of ZIM laser. At last, we calculate the lasing threshold and slope coefficient of the ZIM laser.